American Standard Code for Information Interchange

アスキー・コード 情報交換用米国標準コード

WordNet

1. established or well-known or widely recognized as a model of authority or excellence; "a standard reference work"; "the classical argument between free trade and protectionism"
2. the value behind the money in a monetary system (同)monetary standard
3. a board measure = 1980 board feet
4. any distinctive flag (同)banner
5. an upright pole or beam (especially one used as a support); "distance was marked by standards every mile"; "lamps supported on standards provided illumination"
6. a basis for comparison; a reference point against which other things can be evaluated; "the schools comply with federal standards"; "they set the measure for all subsequent work" (同)criterion, measure, touchstone
7. conforming to the established language usage of educated native speakers; "standard English" (American); "received standard English is sometimes called the Kings English" (British) (同)received
8. regularly and widely used or sold; "a standard size"; "a stock item" (同)stock
9. commonly used or supplied; "standard procedure"; "standard car equipment"
10. conforming to or constituting a standard of measurement or value; or of the usual or regularized or accepted kind; "windows of standard width"; "standard sizes"; "the standard fixtures"; "standard brands"; "standard operating procedure"
11. attach a code to; "Code the pieces with numbers so that you can identify them later"
12. a set of rules or principles or laws (especially written ones) (同)codification
13. (computer science) the symbolic arrangement of data or instructions in a computer program or the set of such instructions (同)computer code
14. a coding system used for transmitting messages requiring brevity or secrecy
15. convert ordinary language into code; "We should encode the message for security reasons" (同)encipher, cipher, cypher, encrypt, inscribe, write in code
16. reverse (a direction, attitude, or course of action) (同)tack, switch, alternate, flip, flip-flop
17. mutual interaction; the activity of reciprocating or exchanging (especially information) (同)reciprocation, give-and-take
18. a junction of highways on different levels that permits traffic to move from one to another without crossing traffic streams
19. of or relating to the United States of America or its people or language or culture; "American citizens"; "American English"; "the American dream"
20. a native or inhabitant of a North American or Central American or South American country
21. a native or inhabitant of the United States
22. of or relating to or characteristic of the continents and islands of the Americas; "the American hemisphere"; "American flora and fauna"

PrepTutorEJDIC

1. 〈C〉〈U〉『標準』,基準,水準,規範 / 〈C〉(度量衡の)基本単位 / 〈U〉〈C〉(貨幣制度の)本位 / 〈C〉旗,軍旗;(主義・主張などの)旗じるし / 〈C〉支桂,ランプ台,しょく台 / 『標準の』,標準的な / 定評のある,権威のある
2. 《時間・距離》『…の間』 / 《利益・貢献》『…のために』 / 《適応・用途》『…向きの(に);』…用の(に);…のための(に) / 《目的・意向》『…のために,』に / 《敬意・記念》『…のために;』…を記念して / 《獲得・追求》『…を得るために』,を求めて / 《行く先・方向》『…あてに;』…[方面]行きの,に向けて / 《交換・報償など》『…に対して』;…と引き換えに;…のお返しに / 《原因・理由》『…のために』,なので / 《代理・代表》『…の代わりに;』…を代表して / 《形容詞の後に用いて》『…にとって,』には / 《比較級の後に用いて》『…の結果として,』…のために / 《対比》『…としては,』のわりには / 《関連》『…について,』の点では / 《資格・属性》『…として』 / 《賛成・支持》…『に賛成して』,を支持して / 《傾向・好み》…『に対する』,には / 《模倣》《おもに米》《英文》…の名を取って(after) / 《割合》…に対して / 《『for』+『名』〈人〉+『to』 doの形で,〈人〉が不定詞to doの意味上の主語を表して》…が(…することは,…するために) / […というのは]…だから
3. 『法典』 / (社会・階級・団体などを支配する)『規約』,おきて,慣例 / 『信号法』;暗号 / 〈通信など〉'を'暗号(信号)にする
4. 〈人が〉〈二つの物など〉‘を'置き換える,〈両者〉‘を'交替させる / 〈二人の人などが〉〈物・事〉‘を'やり取りする,交換する / 〈相互が〉入れ替わる,交替する / 〈U〉〈C〉(意見などの)交換《+『of』+『名』》 / 〈C〉《米》インターチェンジ(高速道路の立体交差地点)
5. 『アメリカ合衆国の』,米国の;アメリカ人の / 北アメリカの;北米人の / 南アメリカの;南米人の / 南北アメリカの;南北アメリカ人の / 米国人,アメリカ人 / 北(南)アメリカ人 / =American English

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/08/14 04:30:17」(JST)

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ASCII（アスキー、英: American Standard Code for Information Interchange）は、現代英語や西ヨーロッパ言語で使われるラテン文字を中心とした文字コード。これはコンピュータその他の通信機器において最もよく使われているものである。

概要

ASCIIは、7桁の2進数で表すことのできる整数の数値のそれぞれに、大小のラテン文字や数字、英文でよく使われる約物などを割り当てた文字コードである。1963年6月17日に、American Standards Association（ASA、後のANSI）によって制定された。当時の規格番号は ASA X3.4 、現在の規格番号は ANSI INCITS 4 である。

ASCIIはISO標準7ビット文字コードISO/IEC 646の元となり、後に8ビット文字コードであるISO/IEC 8859が主流となって以降、世界中で使用されている様々な文字の符号化方式の多くは、ASCIIで使用されていない128番以降の部分に、その他の文字を割り当てたものである。

他の文字コードと同じく、ASCIIは整数で表されるデジタルデータと文字集合とが対応づけられたコードである。このコードに従い、文字等を整数に変換する事で、通信、文字情報の処理や保存を行うのが容易になる。ASCIIやASCII互換コードは、ほとんど全てのコンピュータ（特にパーソナルコンピュータやワークステーション）で扱う事が出来る。MIMEでは、「US-ASCII」とするのが望ましい。

ASCIIは7ビットコードである。つまり、情報を表すのに7桁の2進数（10進数では0〜127）を用いる。ASCIIが規格化された頃ですら、ほとんどのコンピュータの扱う最少単位のバイトは8ビットであるオクテットであった。そのため8ビット目は通信におけるエラーチェック用のパリティビットとして用いられていた。21世紀初頭においても、互換性を維持する目的で、7ビットコードが正式で、8ビット目は使用できない規格がいくつか存在する。

ASCIIはテキストの構造や見た目に関する情報を（基本的に文字コードとしては）持たない（垂直タブや改頁はそういったものの一種と考えられなくもないが、「制御コード」となっている）。そのような情報はマークアップ言語などを使用する事で補うことが出来る。

ASCIIの構成は次のようになっている。

コード範囲（16進）	内容
00-1F	制御文字
20	空白
21-7E	図形文字
7F	制御文字（DEL）

ASCII制御文字

初めの32文字（10進数で0-31）はASCIIでは制御文字として予約されている。基本的にはこれらの制御文字は表示するための文字ではなく、モニタやプリンタなどの機器を制御するために用いられる。例えば、ASCII 10（10進）は line feed（改行）を表し（プリンタの紙送りなどに用いる）、ASCII 27 はエスケープを表す。

ASCII 127（全てのビットがオン、つまり、2進数で1111111）は、delete（削除文字） として知られる制御文字である。この記号が現れた場合、その部分のデータが消去されていることを示す。この制御文字だけ先頭部分になく最後にある理由は、パンチテープへの記録は上書きが出来ないため、削除する際には全てに穴を空けることで対応できるというところからきている（1111111は全てに穴の開いた状態を示す）。また、ASCII 0（全てのビットがオフ、つまり2進数で0000000）は Null あるいはヌル文字と呼ばれ、delete と同様に多くのコンピュータシステムでは無視される。これは、仮にパンチテープと反対に1を0に変えることでデータを記録し、かつ上書きが不可能な媒体が存在する場合でも対応できるようにしているのである。

コードの多くは、データ転送プロトコルで用いられる。（例：ヘッディング開始、テキスト開始、テキスト終了など。）

セパレータは磁気テープへの保存のために設計された。

XON や XOFF は、プリンタのような処理の遅いデバイスにおいて、データを失うことがないように情報の流れを制御するために用いる事がある。

2進	8進	10進	16進	略語	図形表現	CS	エスケープシーケンス	名前/意味
000 0000	000	0	00	NUL	␀	^@	==Wikipedia preview== 出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2018/11/04 20:21:46」(JST) ====[http://ja.wikipedia.org/wiki/American%20Standard%20Code%20for%20Information%20Interchange wiki ja]==== ASCII（アスキー、英: American Standard Code for Information Interchange）は、現代英語や西ヨーロッパ言語で使われるラテン文字を中心とした文字コード。これはコンピュータその他の通信機器において最もよく使われているものである。 概要 ASCIIは、7桁の2進数で表すことのできる整数の数値のそれぞれに、大小のラテン文字や数字、英文でよく使われる約物などを割り当てた文字コードである。1963年6月17日に、American Standards Association（ASA、後のANSI）によって制定された。当時の規格番号は ASA X3.4 、現在の規格番号は ANSI INCITS 4 である。 ASCIIはISO標準7ビット文字コードISO/IEC 646の元となり、後に8ビット文字コードであるISO/IEC 8859が主流となって以降、世界中で使用されている様々な文字の符号化方式の多くは、ASCIIで使用されていない128番以降の部分に、その他の文字を割り当てたものである。 他の文字コードと同じく、ASCIIは整数で表されるデジタルデータと文字集合とが対応づけられたコードである。このコードに従い、文字等を整数に変換する事で、通信、文字情報の処理や保存を行うのが容易になる。ASCIIやASCII互換コードは、ほとんど全てのコンピュータ（特にパーソナルコンピュータやワークステーション）で扱う事が出来る。MIMEでは、「US-ASCII」とするのが望ましい。 ASCIIは7ビットコードである。つまり、情報を表すのに7桁の2進数（10進数では0〜127）を用いる。ASCIIが規格化された頃ですら、ほとんどのコンピュータの扱う最少単位のバイトは8ビットであるオクテットであった。そのため8ビット目は通信におけるエラーチェック用のパリティビットとして用いられていた。21世紀初頭においても、互換性を維持する目的で、7ビットコードが正式で、8ビット目は使用できない規格がいくつか存在する。 ASCIIはテキストの構造や見た目に関する情報を（基本的に文字コードとしては）持たない（垂直タブや改頁はそういったものの一種と考えられなくもないが、「制御コード」となっている）。そのような情報はマークアップ言語などを使用する事で補うことが出来る。 ASCIIの構成は次のようになっている。 コード範囲（16進） 内容 00-1F 制御文字 20 空白 21-7E 図形文字 7F 制御文字（DEL） ASCII制御文字 初めの32文字（10進数で0-31）はASCIIでは制御文字として予約されている。基本的にはこれらの制御文字は表示するための文字ではなく、モニタやプリンタなどの機器を制御するために用いられる。例えば、ASCII 10（10進）は line feed（改行）を表し（プリンタの紙送りなどに用いる）、ASCII 27 はエスケープを表す。 ASCII 127（全てのビットがオン、つまり、2進数で1111111）は、delete（削除文字） として知られる制御文字である。この記号が現れた場合、その部分のデータが消去されていることを示す。この制御文字だけ先頭部分になく最後にある理由は、パンチテープへの記録は上書きが出来ないため、削除する際には全てに穴を空けることで対応できるというところからきている（1111111は全てに穴の開いた状態を示す）。また、ASCII 0（全てのビットがオフ、つまり2進数で0000000）は Null あるいはヌル文字と呼ばれ、delete と同様に多くのコンピュータシステムでは無視される。これは、仮にパンチテープと反対に1を0に変えることでデータを記録し、かつ上書きが不可能な媒体が存在する場合でも対応できるようにしているのである。 コードの多くは、データ転送プロトコルで用いられる。（例：ヘッディング開始、テキスト開始、テキスト終了など。） セパレータは磁気テープへの保存のために設計された。 XON や XOFF は、プリンタのような処理の遅いデバイスにおいて、データを失うことがないように情報の流れを制御するために用いる事がある。 </tbody> 2進 8進 10進 16進 略語 図形表現 CS エスケープシーケンス 名前/意味 000 0000 000 0 00 NUL ␀ ^@ ==Wikipedia preview== 出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2019/01/25 02:09:41」(JST) ====[http://ja.wikipedia.org/wiki/American%20Standard%20Code%20for%20Information%20Interchange wiki ja]==== ASCII（アスキー、英: American Standard Code for Information Interchange）は、現代英語や西ヨーロッパ言語で使われるラテン文字を中心とした文字コード。これはコンピュータその他の通信機器において最もよく使われているものである。 概要 ASCIIは、7桁の2進数で表すことのできる整数の数値のそれぞれに、大小のラテン文字や数字、英文でよく使われる約物などを割り当てた文字コードである。1963年6月17日に、American Standards Association（ASA、後のANSI）によって制定された。当時の規格番号は ASA X3.4 、現在の規格番号は ANSI INCITS 4 である。 ASCIIはISO標準7ビット文字コードISO/IEC 646の元となり、後に8ビット文字コードであるISO/IEC 8859が主流となって以降、世界中で使用されている様々な文字の符号化方式の多くは、ASCIIで使用されていない128番以降の部分に、その他の文字を割り当てたものである。 他の文字コードと同じく、ASCIIは整数で表されるデジタルデータと文字集合とが対応づけられたコードである。このコードに従い、文字等を整数に変換する事で、通信、文字情報の処理や保存を行うのが容易になる。ASCIIやASCII互換コードは、ほとんど全てのコンピュータ（特にパーソナルコンピュータやワークステーション）で扱う事が出来る。MIMEでは、「US-ASCII」とするのが望ましい。 ASCIIは7ビットコードである。つまり、情報を表すのに7桁の2進数（10進数では0〜127）を用いる。ASCIIが規格化された頃ですら、ほとんどのコンピュータの扱う最少単位のバイトは8ビットであるオクテットであった。そのため8ビット目は通信におけるエラーチェック用のパリティビットとして用いられていた。21世紀初頭においても、互換性を維持する目的で、7ビットコードが正式で、8ビット目は使用できない規格がいくつか存在する。 ASCIIはテキストの構造や見た目に関する情報を（基本的に文字コードとしては）持たない（垂直タブや改頁はそういったものの一種と考えられなくもないが、「制御コード」となっている）。そのような情報はマークアップ言語などを使用する事で補うことが出来る。 ASCIIの構成は次のようになっている。 コード範囲（16進） 内容 00-1F 制御文字 20 空白 21-7E 図形文字 7F 制御文字（DEL） ASCII制御文字 初めの32文字（10進数で0-31）はASCIIでは制御文字として予約されている。基本的にはこれらの制御文字は表示するための文字ではなく、モニタやプリンタなどの機器を制御するために用いられる。例えば、ASCII 10（10進）は line feed（改行）を表し（プリンタの紙送りなどに用いる）、ASCII 27 はエスケープを表す。 ASCII 127（全てのビットがオン、つまり、2進数で1111111）は、delete（削除文字） として知られる制御文字である。この記号が現れた場合、その部分のデータが消去されていることを示す。この制御文字だけ先頭部分になく最後にある理由は、パンチテープへの記録は上書きが出来ないため、削除する際には全てに穴を空けることで対応できるというところからきている（1111111は全てに穴の開いた状態を示す）。また、ASCII 0（全てのビットがオフ、つまり2進数で0000000）は Null あるいはヌル文字と呼ばれ、delete と同様に多くのコンピュータシステムでは無視される。これは、仮にパンチテープと反対に1を0に変えることでデータを記録し、かつ上書きが不可能な媒体が存在する場合でも対応できるようにしているのである。 コードの多くは、データ転送プロトコルで用いられる。（例：ヘッディング開始、テキスト開始、テキスト終了など。） セパレータは磁気テープへの保存のために設計された。 XON や XOFF は、プリンタのような処理の遅いデバイスにおいて、データを失うことがないように情報の流れを制御するために用いる事がある。 2進 8進 10進 16進 略語 図形表現 CS エスケープシーケンス 名前/意味 000 0000 000 0 00 NUL ␀ ^@ ヌル文字 000 0001 001 1 01 SOH ␁ ^A ヘッディング開始 000 0010 002 2 02 STX ␂ ^B テキスト開始 000 0011 003 3 03 ETX ␃ ^C テキスト終了 000 0100 004 4 04 EOT ␄ ^D 伝送終了 000 0101 005 5 05 ENQ ␅ ^E 問い合わせ 000 0110 006 6 06 ACK ␆ ^F 肯定応答 000 0111 007 7 07 BEL ␇ ^G \a ベル 000 1000 010 8 08 BS ␈ ^H \b 後退 000 1001 011 9 09 HT ␉ ^I \t 水平タブ 000 1010 012 10 0A LF ␊ ^J \n 改行 000 1011 013 11 0B VT ␋ ^K \v 垂直タブ 000 1100 014 12 0C FF ␌ ^L \f 書式送り 000 1101 015 13 0D CR ␍ ^M \r 復帰 000 1110 016 14 0E SO ␎ ^N シフトアウト 000 1111 017 15 0F SI ␏ ^O シフトイン 001 0000 020 16 10 DLE ␐ ^P 伝送制御拡張 001 0001 021 17 11 DC1 ␑ ^Q 装置制御1、XON 001 0010 022 18 12 DC2 ␒ ^R 装置制御2 001 0011 023 19 13 DC3 ␓ ^S 装置制御3、XOFF 001 0100 024 20 14 DC4 ␔ ^T 装置制御4 001 0101 025 21 15 NAK ␕ ^U 否定応答 001 0110 026 22 16 SYN ␖ ^V 同期信号 001 0111 027 23 17 ETB ␗ ^W 伝送ブロック終結 001 1000 030 24 18 CAN ␘ ^X 取消 001 1001 031 25 19 EM ␙ ^Y 媒体終端 001 1010 032 26 1A SUB ␚ ^Z 置換 001 1011 033 27 1B ESC ␛ ^[ \e エスケープ 001 1100 034 28 1C FS ␜ ^\ ファイル分離標識 001 1101 035 29 1D GS ␝ ^] グループ分離標識 001 1110 036 30 1E RS ␞ ^^ レコード分離標識 001 1111 037 31 1F US ␟ ^_ ユニット分離標識 111 1111 177 127 7F DEL ␡ ^? 抹消 ASCII印字可能文字 ASCII 32は、空白文字である。キーボードのスペースキーから入力でき、語と語の間に空白を表示する。 ASCII 33〜126は印刷可能な文字（printable characters）であり、半角英数の数字、句読点や記号を表す。若い順からエクスクラメーションマーク、ダブルクオーテーション・・・と続き、ラテン文字大文字の前に数字と大半の半角約物、大文字と小文字の間、ラテン文字小文字の後にも数種類の半角約物が割り当てられている。 下の図では、16進数・10進数・8進数の順でASCIIコードの値を示す。 凡例:   アルファベット   制御文字   数字   記号   拡張記号   図形文字   国際   未定義 ASCII (American Standard Code for Information Interchange) 印字可能文字 _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F   2−   SP 0x20 32 040 ! 0x21 33 041 " 0x22 34 042 # 0x23 35 043 $ 0x24 36 044 % 0x25 37 045 & 0x26 38 046 ' 0x27 39 047 ( 0x28 40 050 ) 0x29 41 051 * 0x2A 42 052 + 0x2B 43 053 , 0x2C 44 054 - 0x2D 45 055 . 0x2E 46 056 / 0x2F 47 057   3−   0 0x30 48 060 1 0x31 49 061 2 0x32 50 062 3 0x33 51 063 4 0x34 52 064 5 0x35 53 065 6 0x36 54 066 7 0x37 55 067 8 0x38 56 070 9 0x39 57 071 : 0x3A 58 072 ; 0x3B 59 073 < 0x3C 60 074 = 0x3D 61 075 > 0x3E 62 076 ? 0x3F 63 077   4−   @ 0x40 64 100 A 0x41 65 101 B 0x42 66 102 C 0x43 67 103 D 0x44 68 104 E 0x45 69 105 F 0x46 70 106 G 0x47 71 107 H 0x48 72 110 I 0x49 73 111 J 0x4A 74 112 K 0x4B 75 113 L 0x4C 76 114 M 0x4D 77 115 N 0x4E 78 116 O 0x4F 79 117   5−   P 0x50 80 120 Q 0x51 81 121 R 0x52 82 122 S 0x53 83 123 T 0x54 84 124 U 0x55 85 125 V 0x56 86 126 W 0x57 87 127 X 0x58 88 130 Y 0x59 89 131 Z 0x5A 90 132 [ 0x5B 91 133 \ 0x5C 92 134 ] 0x5D 93 135 ^ 0x5E 94 136 _ 0x5F 95 137   6−   ` 0x60 96 140 a 0x61 97 141 b 0x62 98 142 c 0x63 99 143 d 0x64 100 144 e 0x65 101 145 f 0x66 102 146 g 0x67 103 147 h 0x68 104 150 i 0x69 105 151 j 0x6A 106 152 k 0x6B 107 153 l 0x6C 108 154 m 0x6D 109 155 n 0x6E 110 156 o 0x6F 111 157   7−   p 0x70 112 160 q 0x71 113 161 r 0x72 114 162 s 0x73 115 163 t 0x74 116 164 u 0x75 117 165 v 0x76 118 166 w 0x77 119 167 x 0x78 120 170 y 0x79 121 171 z 0x7A 122 172 { 0x7B 123 173 | 0x7C 124 174 } 0x7D 125 175 ~ 0x7E 126 176 _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F 大文字のASCII値に32を加えると小文字に変換することが出来る。この変換は、2進法では、6ビット目に1をセットするだけでよい。また、数字から48を減じれば、対応する値が得られる。この変換は、5ビット目及び6ビット目に0をセットするか、あるいは単純に上位4ビットを無視するだけでもよい。なお、印字可能文字のうち「@」から始まる32文字については、ASCII値を64減じて対応する制御文字を求め、この制御文字を「コントロール+」（英: control+）という前置表現を付けた印字可能文字で表記する慣習がある。 例：BELコード(07) →「コントロール+G」（受信した側の機器で注意喚起音が鳴る） この制御文字の表記方法は、キーボード上の印字可能文字キーを制御文字の送出に用いていた機器の名残りであると考えられる（7ビット目を0にセットする専用キー（Ctrlキー）を、印字可能文字キーと同時に押して制御文字を送出）。 また，Unix 端末では Ctrl+数字 で人間工学的に押下しづらい制御文字を送出できる。具体的には ^2 が ^@，^3 が ^[，^4 が ^\，^5 が ^]，^6 が ^^，^7 が ^_，^8 が ^? であることが多い。 参考文献 「ANSI INCITS 4-1986 (formerly ANSI X3.4-1986) American National Standard for Information Systems ― Coded Character Sets ― 7-Bit American National Standard Code for Information Interchange (7-Bit ASCII)」American National Standards Institute（1963年6月17日制定、1986年3月26日最終改正、2002年1月15日規格番号変更） 関連項目 JIS X 0201 wiki en [Wiki en表示] Not to be confused with MS Windows-1252 or other types of extended ASCII. This article is about the character encoding. For other uses, see ASCII (disambiguation). ASCII ASCII (1967 or later) MIME / IANA us-ascii Alias(es) ASCII Language(s) English Classification ISO 646 series Extensions Unicode ISO 8859 (series) KOI-8 OEM (series) Windows-125x (series) Others Preceded by ITA 2, FIELDATA Succeeded by ISO 8859, Unicode Other related encoding(s) PETSCII ASCII (/ˈæskiː/ (listen) ASS-kee), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Most modern character-encoding schemes are based on ASCII, although they support many additional characters. ASCII is the traditional name for the encoding system; the Internet Assigned Numbers Authority (IANA) prefers the updated name US-ASCII, which clarifies that this system was developed in the US and based on the typographical symbols predominantly in use there. ASCII is one of the IEEE milestones. ASCII chart from an earlier-than 1972 printer manual (b1 is the least significant bit.) Overview ASCII was developed from telegraph code. Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services. Work on the ASCII standard began on October 6, 1960, with the first meeting of the American Standards Association's (ASA) (now the American National Standards Institute or ANSI) X3.2 subcommittee. The first edition of the standard was published in 1963, underwent a major revision during 1967, and experienced its most recent update during 1986. Compared to earlier telegraph codes, the proposed Bell code and ASCII were both ordered for more convenient sorting (i.e., alphabetization) of lists, and added features for devices other than teleprinters. Originally based on the English alphabet, ASCII encodes 128 specified characters into seven-bit integers as shown by the ASCII chart above. Ninety-five of the encoded characters are printable: these include the digits 0 to 9, lowercase letters a to z, uppercase letters A to Z, and punctuation symbols. In addition, the original ASCII specification included 33 non-printing control codes which originated with Teletype machines; most of these are now obsolete, although a few are still commonly used, such as the carriage return, line feed and tab codes. For example, lowercase i would be represented in the ASCII encoding by binary 1101001 = hexadecimal 69 (i is the ninth letter) = decimal 105. History ASCII (1963). Control pictures of equivalent controls are shown where they exist, or a grey dot otherwise. The American Standard Code for Information Interchange (ASCII) was developed under the auspices of a committee of the American Standards Association (ASA), called the X3 committee, by its X3.2 (later X3L2) subcommittee, and later by that subcommittee's X3.2.4 working group (now INCITS). The ASA became the United States of America Standards Institute (USASI) and ultimately the American National Standards Institute (ANSI). With the other special characters and control codes filled in, ASCII was published as ASA X3.4-1963, leaving 28 code positions without any assigned meaning, reserved for future standardization, and one unassigned control code. There was some debate at the time whether there should be more control characters rather than the lowercase alphabet. The indecision did not last long: during May 1963 the CCITT Working Party on the New Telegraph Alphabet proposed to assign lowercase characters to sticks 6 and 7, and International Organization for Standardization TC 97 SC 2 voted during October to incorporate the change into its draft standard. The X3.2.4 task group voted its approval for the change to ASCII at its May 1963 meeting. Locating the lowercase letters in sticks 6 and 7 caused the characters to differ in bit pattern from the upper case by a single bit, which simplified case-insensitive character matching and the construction of keyboards and printers. The X3 committee made other changes, including other new characters (the brace and vertical bar characters), renaming some control characters (SOM became start of header (SOH)) and moving or removing others (RU was removed). ASCII was subsequently updated as USAS X3.4-1967, then USAS X3.4-1968, ANSI X3.4-1977, and finally, ANSI X3.4-1986. Revisions of the ASCII standard: ASA X3.4-1963 ASA X3.4-1965 (approved, but not published, nevertheless used by IBM 2260 & 2265 Display Stations and IBM 2848 Display Control) USAS X3.4-1967 USAS X3.4-1968 ANSI X3.4-1977 ANSI X3.4-1986 ANSI X3.4-1986 (R1992) ANSI X3.4-1986 (R1997) ANSI INCITS 4-1986 (R2002) ANSI INCITS 4-1986 (R2007) ANSI INCITS 4-1986 (R2012) In the X3.15 standard, the X3 committee also addressed how ASCII should be transmitted (least significant bit first), and how it should be recorded on perforated tape. They proposed a 9-track standard for magnetic tape, and attempted to deal with some punched card formats. Design considerations Bit width The X3.2 subcommittee designed ASCII based on the earlier teleprinter encoding systems. Like other character encodings, ASCII specifies a correspondence between digital bit patterns and character symbols (i.e. graphemes and control characters). This allows digital devices to communicate with each other and to process, store, and communicate character-oriented information such as written language. Before ASCII was developed, the encodings in use included 26 alphabetic characters, 10 numerical digits, and from 11 to 25 special graphic symbols. To include all these, and control characters compatible with the Comité Consultatif International Téléphonique et Télégraphique (CCITT) International Telegraph Alphabet No. 2 (ITA2) standard of 1924, FIELDATA (1956), and early EBCDIC (1963), more than 64 codes were required for ASCII. ITA2 were in turn based on the 5-bit telegraph code Émile Baudot invented in 1870 and patented in 1874. The committee debated the possibility of a shift function (like in ITA2), which would allow more than 64 codes to be represented by a six-bit code. In a shifted code, some character codes determine choices between options for the following character codes. It allows compact encoding, but is less reliable for data transmission, as an error in transmitting the shift code typically makes a long part of the transmission unreadable. The standards committee decided against shifting, and so ASCII required at least a seven-bit code. The committee considered an eight-bit code, since eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal. However, it would require all data transmission to send eight bits when seven could suffice. The committee voted to use a seven-bit code to minimize costs associated with data transmission. Since perforated tape at the time could record eight bits in one position, it also allowed for a parity bit for error checking if desired. Eight-bit machines (with octets as the native data type) that did not use parity checking typically set the eighth bit to 0. In some printers, the high bit was used to enable Italics printing. Internal organization The code itself was patterned so that most control codes were together and all graphic codes were together, for ease of identification. The first two so called ASCII sticks (32 positions) were reserved for control characters. The "space" character had to come before graphics to make sorting easier, so it became position 20hex; for the same reason, many special signs commonly used as separators were placed before digits. The committee decided it was important to support uppercase 64-character alphabets, and chose to pattern ASCII so it could be reduced easily to a usable 64-character set of graphic codes, as was done in the DEC SIXBIT code (1963). Lowercase letters were therefore not interleaved with uppercase. To keep options available for lowercase letters and other graphics, the special and numeric codes were arranged before the letters, and the letter A was placed in position 41hex to match the draft of the corresponding British standard. The digits 0–9 are prefixed with 011, but the remaining 4 bits correspond to their respective values in binary, making conversion with binary-coded decimal straightforward. Many of the non-alphanumeric characters were positioned to correspond to their shifted position on typewriters; an important subtlety is that these were based on mechanical typewriters, not electric typewriters. Mechanical typewriters followed the standard set by the Remington No. 2 (1878), the first typewriter with a shift key, and the shifted values of 23456789- were "#$%_&'() – early typewriters omitted 0 and 1, using O (capital letter o) and l (lowercase letter L) instead, but 1! and 0) pairs became standard once 0 and 1 became common. Thus, in ASCII !"#$% were placed in the second stick, positions 1–5, corresponding to the digits 1–5 in the adjacent stick. The parentheses could not correspond to 9 and 0, however, because the place corresponding to 0 was taken by the space character. This was accommodated by removing _ (underscore) from 6 and shifting the remaining characters, which corresponded to many European typewriters that placed the parentheses with 8 and 9. This discrepancy from typewriters led to bit-paired keyboards, notably the Teletype Model 33, which used the left-shifted layout corresponding to ASCII, not to traditional mechanical typewriters. Electric typewriters, notably the IBM Selectric (1961), used a somewhat different layout that has become standard on computers – following the IBM PC (1981), especially Model M (1984) – and thus shift values for symbols on modern keyboards do not correspond as closely to the ASCII table as earlier keyboards did. The /? pair also dates to the No. 2, and the ,< .> pairs were used on some keyboards (others, including the No. 2, did not shift , (comma) or . (full stop) so they could be used in uppercase without unshifting). However, ASCII split the ;: pair (dating to No. 2), and rearranged mathematical symbols (varied conventions, commonly -* =+) to :* ;+ -=. Some common characters were not included, notably ½¼¢, while ^`~ were included as diacritics for international use, and <> for mathematical use, together with the simple line characters \| (in addition to common /). The @ symbol was not used in continental Europe and the committee expected it would be replaced by an accented À in the French variation, so the @ was placed in position 40hex, right before the letter A. The control codes felt essential for data transmission were the start of message (SOM), end of address (EOA), end of message (EOM), end of transmission (EOT), "who are you?" (WRU), "are you?" (RU), a reserved device control (DC0), synchronous idle (SYNC), and acknowledge (ACK). These were positioned to maximize the Hamming distance between their bit patterns. Character order ASCII-code order is also called ASCIIbetical order. Collation of data is sometimes done in this order rather than "standard" alphabetical order (collating sequence). The main deviations in ASCII order are: All uppercase come before lowercase letters; for example, "Z" precedes "a" Digits and many punctuation marks come before letters An intermediate order converts uppercase letters to lowercase before comparing ASCII values. Character groups Control characters Main article: Control character ASCII reserves the first 32 codes (numbers 0–31 decimal) for control characters: codes originally intended not to represent printable information, but rather to control devices (such as printers) that make use of ASCII, or to provide meta-information about data streams such as those stored on magnetic tape. For example, character 10 represents the "line feed" function (which causes a printer to advance its paper), and character 8 represents "backspace". RFC 2822 refers to control characters that do not include carriage return, line feed or white space as non-whitespace control characters. Except for the control characters that prescribe elementary line-oriented formatting, ASCII does not define any mechanism for describing the structure or appearance of text within a document. Other schemes, such as markup languages, address page and document layout and formatting. The original ASCII standard used only short descriptive phrases for each control character. The ambiguity this caused was sometimes intentional, for example where a character would be used slightly differently on a terminal link than on a data stream, and sometimes accidental, for example with the meaning of "delete". Probably the most influential single device on the interpretation of these characters was the Teletype Model 33 ASR, which was a printing terminal with an available paper tape reader/punch option. Paper tape was a very popular medium for long-term program storage until the 1980s, less costly and in some ways less fragile than magnetic tape. In particular, the Teletype Model 33 machine assignments for codes 17 (Control-Q, DC1, also known as XON), 19 (Control-S, DC3, also known as XOFF), and 127 (Delete) became de facto standards. The Model 33 was also notable for taking the description of Control-G (code 7, BEL, meaning audibly alert the operator) literally, as the unit contained an actual bell which it rang when it received a BEL character. Because the keytop for the O key also showed a left-arrow symbol (from ASCII-1963, which had this character instead of underscore), a noncompliant use of code 15 (Control-O, Shift In) interpreted as "delete previous character" was also adopted by many early timesharing systems but eventually became neglected. When a Teletype 33 ASR equipped with the automatic paper tape reader received a Control-S (XOFF, an abbreviation for transmit off), it caused the tape reader to stop; receiving Control-Q (XON, "transmit on") caused the tape reader to resume. This technique became adopted by several early computer operating systems as a "handshaking" signal warning a sender to stop transmission because of impending overflow; it persists to this day in many systems as a manual output control technique. On some systems Control-S retains its meaning but Control-Q is replaced by a second Control-S to resume output. The 33 ASR also could be configured to employ Control-R (DC2) and Control-T (DC4) to start and stop the tape punch; on some units equipped with this function, the corresponding control character lettering on the keycap above the letter was TAPE and TAPE respectively. The Teletype could not move the head backwards, so it did not put a key on the keyboard to send a BS (backspace). Instead there was a key marked "rubout" that sent code 127 (DEL). The purpose of this key was to erase mistakes in a hand-typed paper tape: the operator had to push a button on the tape punch to back it up, then type the rubout, which punched all holes and replaced the mistake with a character that was intended to be ignored. Teletypes were commonly used for the less-expensive computers from Digital Equipment Corporation, so these systems had to use the available key and thus the DEL code to erase the previous character. Because of this, DEC video terminals (by default) sent the DEL code for the key marked "Backspace" while the key marked "Delete" sent an escape sequence, while many other terminals sent BS for the Backspace key. The Unix terminal driver could only use one code to back up, this could be set to BS or DEL, but not both, resulting in a very long period of annoyance where you had to correct it depending on what terminal you were using (modern shells using readline understand both codes). The assumption that no key sent a BS caused Control+H to be used for other purposes, such as a "help" command in Emacs. Many more of the control codes have been given meanings quite different from their original ones. The "escape" character (ESC, code 27), for example, was intended originally to allow sending other control characters as literals instead of invoking their meaning. This is the same meaning of "escape" encountered in URL encodings, C language strings, and other systems where certain characters have a reserved meaning. Over time this meaning has been co-opted and has eventually been changed. In modern use, an ESC sent to the terminal usually indicates the start of a command sequence usually in the form of a so-called "ANSI escape code" (or, more properly, a "Control Sequence Introducer") from ECMA-48 (1972) and its successors, beginning with ESC followed by a "[" (left-bracket) character. An ESC sent from the terminal is most often used as an out-of-band character used to terminate an operation, as in the TECO and vi text editors. In graphical user interface (GUI) and windowing systems, ESC generally causes an application to abort its current operation or to exit (terminate) altogether. The inherent ambiguity of many control characters, combined with their historical usage, created problems when transferring "plain text" files between systems. The best example of this is the newline problem on various operating systems. Teletype machines required that a line of text be terminated with both "Carriage Return" (which moves the printhead to the beginning of the line) and "Line Feed" (which advances the paper one line without moving the printhead). The name "Carriage Return" comes from the fact that on a manual typewriter the carriage holding the paper moved while the position where the typebars struck the ribbon remained stationary. The entire carriage had to be pushed (returned) to the right in order to position the left margin of the paper for the next line. DEC operating systems (OS/8, RT-11, RSX-11, RSTS, TOPS-10, etc.) used both characters to mark the end of a line so that the console device (originally Teletype machines) would work. By the time so-called "glass TTYs" (later called CRTs or terminals) came along, the convention was so well established that backward compatibility necessitated continuing the convention. When Gary Kildall created CP/M he was inspired by some command line interface conventions used in DEC's RT-11. Until the introduction of PC DOS in 1981, IBM had no hand in this because their 1970s operating systems used EBCDIC instead of ASCII and they were oriented toward punch-card input and line printer output on which the concept of carriage return was meaningless. IBM's PC DOS (also marketed as MS-DOS by Microsoft) inherited the convention by virtue of being loosely based on CP/M, and Windows inherited it from MS-DOS. Unfortunately, requiring two characters to mark the end of a line introduces unnecessary complexity and questions as to how to interpret each character when encountered alone. To simplify matters plain text data streams, including files, on Multics used line feed (LF) alone as a line terminator. Unix and Unix-like systems, and Amiga systems, adopted this convention from Multics. The original Macintosh OS, Apple DOS, and ProDOS, on the other hand, used carriage return (CR) alone as a line terminator; however, since Apple replaced these operating systems with the Unix-based macOS operating system, they now use line feed (LF) as well. The Radio Shack TRS-80 also used a lone CR to terminate lines. Computers attached to the ARPANET included machines running operating systems such as TOPS-10 and TENEX using CR-LF line endings, machines running operating systems such as Multics using LF line endings, and machines running operating systems such as OS/360 that represented lines as a character count followed by the characters of the line and that used EBCDIC rather than ASCII. The Telnet protocol defined an ASCII "Network Virtual Terminal" (NVT), so that connections between hosts with different line-ending conventions and character sets could be supported by transmitting a standard text format over the network. Telnet used ASCII along with CR-LF line endings, and software using other conventions would translate between the local conventions and the NVT. The File Transfer Protocol adopted the Telnet protocol, including use of the Network Virtual Terminal, for use when transmitting commands and transferring data in the default ASCII mode. This adds complexity to implementations of those protocols, and to other network protocols, such as those used for E-mail and the World Wide Web, on systems not using the NVT's CR-LF line-ending convention. The PDP-6 monitor, and its PDP-10 successor TOPS-10, used Control-Z (SUB) as an end-of-file indication for input from a terminal. Some operating systems such as CP/M tracked file length only in units of disk blocks and used Control-Z to mark the end of the actual text in the file. For these reasons, EOF, or end-of-file, was used colloquially and conventionally as a three-letter acronym for Control-Z instead of SUBstitute. The end-of-text code (ETX), also known as Control-C, was inappropriate for a variety of reasons, while using Z as the control code to end a file is analogous to it ending the alphabet and serves as a very convenient mnemonic aid. A historically common and still prevalent convention uses the ETX code convention to interrupt and halt a program via an input data stream, usually from a keyboard. In C library and Unix conventions, the null character is used to terminate text strings; such null-terminated strings can be known in abbreviation as ASCIZ or ASCIIZ, where here Z stands for "zero". Binary Oct Dec Hex Abbreviation Name (1967) 1963 1965 1967 000 0000 000 0 00 NULL NUL ␀ ^@ Null 000 0001 001 1 01 SOM SOH ␁ ^A Start of Heading 000 0010 002 2 02 EOA STX ␂ ^B Start of Text 000 0011 003 3 03 EOM ETX ␃ ^C End of Text 000 0100 004 4 04 EOT ␄ ^D End of Transmission 000 0101 005 5 05 WRU ENQ ␅ ^E Enquiry 000 0110 006 6 06 RU ACK ␆ ^F Acknowledgement 000 0111 007 7 07 BELL BEL ␇ ^G \a Bell 000 1000 010 8 08 FE0 BS ␈ ^H \b Backspace 000 1001 011 9 09 HT/SK HT ␉ ^I \t Horizontal Tab 000 1010 012 10 0A LF ␊ ^J \n Line Feed 000 1011 013 11 0B VTAB VT ␋ ^K \v Vertical Tab 000 1100 014 12 0C FF ␌ ^L \f Form Feed 000 1101 015 13 0D CR ␍ ^M \r Carriage Return 000 1110 016 14 0E SO ␎ ^N Shift Out 000 1111 017 15 0F SI ␏ ^O Shift In 001 0000 020 16 10 DC0 DLE ␐ ^P Data Link Escape 001 0001 021 17 11 DC1 ␑ ^Q Device Control 1 (often XON) 001 0010 022 18 12 DC2 ␒ ^R Device Control 2 001 0011 023 19 13 DC3 ␓ ^S Device Control 3 (often XOFF) 001 0100 024 20 14 DC4 ␔ ^T Device Control 4 001 0101 025 21 15 ERR NAK ␕ ^U Negative Acknowledgement 001 0110 026 22 16 SYNC SYN ␖ ^V Synchronous Idle 001 0111 027 23 17 LEM ETB ␗ ^W End of Transmission Block 001 1000 030 24 18 S0 CAN ␘ ^X Cancel 001 1001 031 25 19 S1 EM ␙ ^Y End of Medium 001 1010 032 26 1A S2 SS SUB ␚ ^Z Substitute 001 1011 033 27 1B S3 ESC ␛ ^[ \e Escape 001 1100 034 28 1C S4 FS ␜ ^\ File Separator 001 1101 035 29 1D S5 GS ␝ ^] Group Separator 001 1110 036 30 1E S6 RS ␞ ^^ Record Separator 001 1111 037 31 1F S7 US ␟ ^_ Unit Separator 111 1111 177 127 7F DEL ␡ ^? Delete Other representations might be used by specialist equipment, for example ISO 2047 graphics or hexadecimal numbers. Printable characters Codes 20hex to 7Ehex, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. There are 95 printable characters in total. Code 20hex, the "space" character, denotes the space between words, as produced by the space bar of a keyboard. Since the space character is considered an invisible graphic (rather than a control character) it is listed in the table below instead of in the previous section. Code 7Fhex corresponds to the non-printable "delete" (DEL) control character and is therefore omitted from this chart; it is covered in the previous section's chart. Earlier versions of ASCII used the up arrow instead of the caret (5Ehex) and the left arrow instead of the underscore (5Fhex). Binary Oct Dec Hex Glyph 1963 1965 1967 010 0000 040 32 20  space 010 0001 041 33 21 ! 010 0010 042 34 22 " 010 0011 043 35 23 # 010 0100 044 36 24 $ 010 0101 045 37 25 % 010 0110 046 38 26 & 010 0111 047 39 27 ' 010 1000 050 40 28 ( 010 1001 051 41 29 ) 010 1010 052 42 2A * 010 1011 053 43 2B + 010 1100 054 44 2C , 010 1101 055 45 2D - 010 1110 056 46 2E . 010 1111 057 47 2F / 011 0000 060 48 30 0 011 0001 061 49 31 1 011 0010 062 50 32 2 011 0011 063 51 33 3 011 0100 064 52 34 4 011 0101 065 53 35 5 011 0110 066 54 36 6 011 0111 067 55 37 7 011 1000 070 56 38 8 011 1001 071 57 39 9 011 1010 072 58 3A : 011 1011 073 59 3B ; 011 1100 074 60 3C < 011 1101 075 61 3D = 011 1110 076 62 3E > 011 1111 077 63 3F ? 100 0000 100 64 40 @ ` @ 100 0001 101 65 41 A 100 0010 102 66 42 B 100 0011 103 67 43 C 100 0100 104 68 44 D 100 0101 105 69 45 E 100 0110 106 70 46 F 100 0111 107 71 47 G 100 1000 110 72 48 H 100 1001 111 73 49 I 100 1010 112 74 4A J 100 1011 113 75 4B K 100 1100 114 76 4C L 100 1101 115 77 4D M 100 1110 116 78 4E N 100 1111 117 79 4F O 101 0000 120 80 50 P 101 0001 121 81 51 Q 101 0010 122 82 52 R 101 0011 123 83 53 S 101 0100 124 84 54 T 101 0101 125 85 55 U 101 0110 126 86 56 V 101 0111 127 87 57 W 101 1000 130 88 58 X 101 1001 131 89 59 Y 101 1010 132 90 5A Z 101 1011 133 91 5B [ 101 1100 134 92 5C \ ~ \ 101 1101 135 93 5D ] 101 1110 136 94 5E ↑ ^ 101 1111 137 95 5F ← _ 110 0000 140 96 60 @ ` 110 0001 141 97 61 a 110 0010 142 98 62 b 110 0011 143 99 63 c 110 0100 144 100 64 d 110 0101 145 101 65 e 110 0110 146 102 66 f 110 0111 147 103 67 g 110 1000 150 104 68 h 110 1001 151 105 69 i 110 1010 152 106 6A j 110 1011 153 107 6B k 110 1100 154 108 6C l 110 1101 155 109 6D m 110 1110 156 110 6E n 110 1111 157 111 6F o 111 0000 160 112 70 p 111 0001 161 113 71 q 111 0010 162 114 72 r 111 0011 163 115 73 s 111 0100 164 116 74 t 111 0101 165 117 75 u 111 0110 166 118 76 v 111 0111 167 119 77 w 111 1000 170 120 78 x 111 1001 171 121 79 y 111 1010 172 122 7A z 111 1011 173 123 7B { 111 1100 174 124 7C ACK ¬ | 111 1101 175 125 7D } 111 1110 176 126 7E ESC | ~ Character set ASCII (1977/1986) _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F 0_ 0 NUL 0000 SOH 0001 STX 0002 ETX 0003 EOT 0004 ENQ 0005 ACK 0006 BEL 0007 BS 0008 HT 0009 LF 000A VT 000B FF 000C CR 000D SO 000E SI 000F 1_ 16 DLE 0010 DC1 0011 DC2 0012 DC3 0013 DC4 0014 NAK 0015 SYN 0016 ETB 0017 CAN 0018 EM 0019 SUB 001A ESC 001B FS 001C GS 001D RS 001E US 001F 2_ 32 SP 0020 ! 0021 " 0022 # 0023 $ 0024 % 0025 & 0026 ' 0027 ( 0028 ) 0029 * 002A + 002B , 002C - 002D . 002E / 002F 3_ 48 0 0030 1 0031 2 0032 3 0033 4 0034 5 0035 6 0036 7 0037 8 0038 9 0039 : 003A ; 003B < 003C = 003D > 003E ? 003F 4_ 64 @ 0040 A 0041 B 0042 C 0043 D 0044 E 0045 F 0046 G 0047 H 0048 I 0049 J 004A K 004B L 004C M 004D N 004E O 004F 5_ 80 P 0050 Q 0051 R 0052 S 0053 T 0054 U 0055 V 0056 W 0057 X 0058 Y 0059 Z 005A [ 005B \ 005C ] 005D ^ 005E _ 005F 6_ 96 ` 0060 a 0061 b 0062 c 0063 d 0064 e 0065 f 0066 g 0067 h 0068 i 0069 j 006A k 006B l 006C m 006D n 006E o 006F 7_ 112 p 0070 q 0071 r 0072 s 0073 t 0074 u 0075 v 0076 w 0077 x 0078 y 0079 z 007A { 007B | 007C } 007D ~ 007E DEL 007F   Letter   Number   Punctuation   Symbol   Other   undefined   Changed from 1963 version Use ASCII was first used commercially during 1963 as a seven-bit teleprinter code for American Telephone & Telegraph's TWX (TeletypeWriter eXchange) network. TWX originally used the earlier five-bit ITA2, which was also used by the competing Telex teleprinter system. Bob Bemer introduced features such as the escape sequence. His British colleague Hugh McGregor Ross helped to popularize this work – according to Bemer, "so much so that the code that was to become ASCII was first called the Bemer–Ross Code in Europe". Because of his extensive work on ASCII, Bemer has been called "the father of ASCII". On March 11, 1968, U.S. President Lyndon B. Johnson mandated that all computers purchased by the United States Federal Government support ASCII, stating: I have also approved recommendations of the Secretary of Commerce [Luther H. Hodges] regarding standards for recording the Standard Code for Information Interchange on magnetic tapes and paper tapes when they are used in computer operations. All computers and related equipment configurations brought into the Federal Government inventory on and after July 1, 1969, must have the capability to use the Standard Code for Information Interchange and the formats prescribed by the magnetic tape and paper tape standards when these media are used. ASCII was the most common character encoding on the World Wide Web until December 2007, when UTF-8 encoding surpassed it; UTF-8 is backward compatible with ASCII. Variants and derivations As computer technology spread throughout the world, different standards bodies and corporations developed many variations of ASCII to facilitate the expression of non-English languages that used Roman-based alphabets. One could class some of these variations as "ASCII extensions", although some misuse that term to represent all variants, including those that do not preserve ASCII's character-map in the 7-bit range. Furthermore, the ASCII extensions have also been mislabelled as ASCII. 7-bit codes Main articles: ECMA-6, ISO/IEC 646, and ITU T.50 See also: UTF-7 From early in its development, ASCII was intended to be just one of several national variants of an international character code standard. Other international standards bodies have ratified character encodings such as ISO 646 (1967) that are identical or nearly identical to ASCII, with extensions for characters outside the English alphabet and symbols used outside the United States, such as the symbol for the United Kingdom's pound sterling (£). Almost every country needed an adapted version of ASCII, since ASCII suited the needs of only the US and a few other countries. For example, Canada had its own version that supported French characters. Many other countries developed variants of ASCII to include non-English letters (e.g. é, ñ, ß, Ł), currency symbols (e.g. £, ¥), etc. See also YUSCII (Yugoslavia). It would share most characters in common, but assign other locally useful characters to several code points reserved for "national use". However, the four years that elapsed between the publication of ASCII-1963 and ISO's first acceptance of an international recommendation during 1967 caused ASCII's choices for the national use characters to seem to be de facto standards for the world, causing confusion and incompatibility once other countries did begin to make their own assignments to these code points. ISO/IEC 646, like ASCII, is a 7-bit character set. It does not make any additional codes available, so the same code points encoded different characters in different countries. Escape codes were defined to indicate which national variant applied to a piece of text, but they were rarely used, so it was often impossible to know what variant to work with and, therefore, which character a code represented, and in general, text-processing systems could cope with only one variant anyway. Because the bracket and brace characters of ASCII were assigned to "national use" code points that were used for accented letters in other national variants of ISO/IEC 646, a German, French, or Swedish, etc. programmer using their national variant of ISO/IEC 646, rather than ASCII, had to write, and thus read, something such as ä aÄiÜ = 'Ön'; ü instead of { a[i] = '\n'; } C trigraphs were created to solve this problem for ANSI C, although their late introduction and inconsistent implementation in compilers limited their use. Many programmers kept their computers on US-ASCII, so plain-text in Swedish, German etc. (for example, in e-mail or Usenet) contained "{, }" and similar variants in the middle of words, something those programmers got used to. For example, a Swedish programmer mailing another programmer asking if they should go for lunch, could get "N{ jag har sm|rg}sar" as the answer, which should be "Nä jag har smörgåsar" meaning "No I've got sandwiches". 8-bit codes Main articles: Extended ASCII and ISO/IEC 8859 See also: UTF-8 Eventually, as 8-, 16- and 32-bit (and later 64-bit) computers began to replace 12-, 18- and 36-bit computers as the norm, it became common to use an 8-bit byte to store each character in memory, providing an opportunity for extended, 8-bit relatives of ASCII. In most cases these developed as true extensions of ASCII, leaving the original character-mapping intact, but adding additional character definitions after the first 128 (i.e., 7-bit) characters. Encodings include ISCII (India), VISCII (Vietnam). Although these encodings are sometimes referred to as ASCII, true ASCII is defined strictly only by the ANSI standard. Most early home computer systems developed their own 8-bit character sets containing line-drawing and game glyphs, and often filled in some or all of the control characters from 0 to 31 with more graphics. Kaypro CP/M computers used the "upper" 128 characters for the Greek alphabet. The PETSCII code Commodore International used for their 8-bit systems is probably unique among post-1970 codes in being based on ASCII-1963, instead of the more common ASCII-1967, such as found on the ZX Spectrum computer. Atari 8-bit computers and Galaksija computers also used ASCII variants. The IBM PC defined code page 437, which replaced the control characters with graphic symbols such as smiley faces, and mapped additional graphic characters to the upper 128 positions. Operating systems such as DOS supported these code pages, and manufacturers of IBM PCs supported them in hardware. Digital Equipment Corporation developed the Multinational Character Set (DEC-MCS) for use in the popular VT220 terminal as one of the first extensions designed more for international languages than for block graphics. The Macintosh defined Mac OS Roman and Postscript also defined a set, both of these contained both international letters and typographic punctuation marks instead of graphics, more like modern character sets. The ISO/IEC 8859 standard (derived from the DEC-MCS) finally provided a standard that most systems copied (at least as accurately as they copied ASCII, but with many substitutions). A popular further extension designed by Microsoft, Windows-1252 (often mislabeled as ISO-8859-1), added the typographic punctuation marks needed for traditional text printing. ISO-8859-1, Windows-1252, and the original 7-bit ASCII were the most common character encodings until 2008 when UTF-8 became more common. ISO/IEC 4873 introduced 32 additional control codes defined in the 80–9F hexadecimal range, as part of extending the 7-bit ASCII encoding to become an 8-bit system. Unicode Main articles: Unicode and ISO/IEC 10646 See also: Basic Latin (Unicode block) Unicode and the ISO/IEC 10646 Universal Character Set (UCS) have a much wider array of characters and their various encoding forms have begun to supplant ISO/IEC 8859 and ASCII rapidly in many environments. While ASCII is limited to 128 characters, Unicode and the UCS support more characters by separating the concepts of unique identification (using natural numbers called code points) and encoding (to 8-, 16- or 32-bit binary formats, called UTF-8, UTF-16 and UTF-32). ASCII was incorporated into the Unicode (1991) character set as the first 128 symbols, so the 7-bit ASCII characters have the same numeric codes in both sets. This allows UTF-8 to be backward compatible with 7-bit ASCII, as a UTF-8 file containing only ASCII characters is identical to an ASCII file containing the same sequence of characters. Even more importantly, forward compatibility is ensured as software that recognizes only 7-bit ASCII characters as special and does not alter bytes with the highest bit set (as is often done to support 8-bit ASCII extensions such as ISO-8859-1) will preserve UTF-8 data unchanged. See also 3568 ASCII, an asteroid named after the character encoding Ascii85 ASCII art ASCII Ribbon Campaign Basic Latin (Unicode block) (ASCII as a subset of Unicode) Extended ASCII HTML decimal character rendering List of Unicode characters Jargon File, a glossary of computer programmer slang which includes a list of common slang names for ASCII characters List of computer character sets Alt codes Further reading Bemer, Robert William (1960). "A Proposal for Character Code Compatibility". Communications of the ACM. 3 (2): 71–72. doi:10.1145/366959.366961. Bemer, Robert William (2003-05-23). "The Babel of Codes Prior to ASCII: The 1960 Survey of Coded Character Sets: The Reasons for ASCII". Archived from the original on 2013-10-17. Retrieved 2016-05-09, from: Bemer, Robert William (December 1960). "Survey of coded character representation". Communications of the ACM. 3 (12): 639–641. doi:10.1145/367487.367493. Smith, H. J.; Williams, F. A. (December 1960). "Survey of punched card codes". Communications of the ACM. 3 (12): 642. doi:10.1145/367487.367491. American National Standard Code for Information Interchange. American National Standards Institute. 1977. Robinson, G. S.; Cargill, C. (1996). "History and impact of computer standards". Computer. 29 (10): 79–85. doi:10.1109/2.539725. Mullendore, Ralph Elvin (1964) [1963]. Ptak, John F., ed. "On the Early Development of ASCII – The History of ASCII". JF Ptak Science Books (published March 2012). Archived from the original on 2016-05-26. Retrieved 2016-05-26. External links "C0 Controls and Basic Latin – Range: 0000–007F" (PDF). The Unicode Standard 8.0. Unicode, Inc. 2015 [1991]. Archived (PDF) from the original on 2016-05-26. Retrieved 2016-05-26. Fischer, Eric. "The Evolution of Character Codes, 1874–1968". Retrieved 2016-05-26. [1] ヌル文字 000 0001 001 1 01 SOH ␁ ^A ヘッディング開始 000 0010 002 2 02 STX ␂ ^B テキスト開始 000 0011 003 3 03 ETX ␃ ^C テキスト終了 000 0100 004 4 04 EOT ␄ ^D 伝送終了 000 0101 005 5 05 ENQ ␅ ^E 問い合わせ 000 0110 006 6 06 ACK ␆ ^F 肯定応答 000 0111 007 7 07 BEL ␇ ^G \a ベル 000 1000 010 8 08 BS ␈ ^H \b 後退 000 1001 011 9 09 HT ␉ ^I \t 水平タブ 000 1010 012 10 0A LF ␊ ^J \n 改行 000 1011 013 11 0B VT ␋ ^K \v 垂直タブ 000 1100 014 12 0C FF ␌ ^L \f 書式送り 000 1101 015 13 0D CR ␍ ^M \r 復帰 000 1110 016 14 0E SO ␎ ^N シフトアウト 000 1111 017 15 0F SI ␏ ^O シフトイン 001 0000 020 16 10 DLE ␐ ^P 伝送制御拡張 001 0001 021 17 11 DC1 ␑ ^Q 装置制御1、XON 001 0010 022 18 12 DC2 ␒ ^R 装置制御2 001 0011 023 19 13 DC3 ␓ ^S 装置制御3、XOFF 001 0100 024 20 14 DC4 ␔ ^T 装置制御4 001 0101 025 21 15 NAK ␕ ^U 否定応答 001 0110 026 22 16 SYN ␖ ^V 同期信号 001 0111 027 23 17 ETB ␗ ^W 伝送ブロック終結 001 1000 030 24 18 CAN ␘ ^X 取消 001 1001 031 25 19 EM ␙ ^Y 媒体終端 001 1010 032 26 1A SUB ␚ ^Z 置換 001 1011 033 27 1B ESC ␛ ^[ \e エスケープ 001 1100 034 28 1C FS ␜ ^\ ファイル分離標識 001 1101 035 29 1D GS ␝ ^] グループ分離標識 001 1110 036 30 1E RS ␞ ^^ レコード分離標識 001 1111 037 31 1F US ␟ ^_ ユニット分離標識 111 1111 177 127 7F DEL ␡ ^? 抹消 ASCII印字可能文字 ASCII 32は、空白文字である。キーボードのスペースキーから入力でき、語と語の間に空白を表示する。 ASCII 33〜126は印刷可能な文字（printable characters）であり、半角英数の数字、句読点や記号を表す。若い順からエクスクラメーションマーク、ダブルクオーテーション・・・と続き、ラテン文字大文字の前に数字と大半の半角約物、大文字と小文字の間、ラテン文字小文字の後にも数種類の半角約物が割り当てられている。 下の図では、16進数・10進数・8進数の順でASCIIコードの値を示す。 凡例: <tbody></tbody>   アルファベット   制御文字   数字   記号   拡張記号   図形文字   国際   未定義 <tbody></tbody> ASCII (American Standard Code for Information Interchange) 印字可能文字 _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F   2−   SP 0x20 32 040 ! 0x21 33 041 " 0x22 34 042 # 0x23 35 043 $ 0x24 36 044 % 0x25 37 045 & 0x26 38 046 ' 0x27 39 047 ( 0x28 40 050 ) 0x29 41 051 * 0x2A 42 052 + 0x2B 43 053 , 0x2C 44 054 - 0x2D 45 055 . 0x2E 46 056 / 0x2F 47 057   3−   0 0x30 48 060 1 0x31 49 061 2 0x32 50 062 3 0x33 51 063 4 0x34 52 064 5 0x35 53 065 6 0x36 54 066 7 0x37 55 067 8 0x38 56 070 9 0x39 57 071 : 0x3A 58 072 ; 0x3B 59 073 < 0x3C 60 074 = 0x3D 61 075 > 0x3E 62 076 ? 0x3F 63 077   4−   @ 0x40 64 100 A 0x41 65 101 B 0x42 66 102 C 0x43 67 103 D 0x44 68 104 E 0x45 69 105 F 0x46 70 106 G 0x47 71 107 H 0x48 72 110 I 0x49 73 111 J 0x4A 74 112 K 0x4B 75 113 L 0x4C 76 114 M 0x4D 77 115 N 0x4E 78 116 O 0x4F 79 117   5−   P 0x50 80 120 Q 0x51 81 121 R 0x52 82 122 S 0x53 83 123 T 0x54 84 124 U 0x55 85 125 V 0x56 86 126 W 0x57 87 127 X 0x58 88 130 Y 0x59 89 131 Z 0x5A 90 132 [ 0x5B 91 133 \ 0x5C 92 134 ] 0x5D 93 135 ^ 0x5E 94 136 _ 0x5F 95 137   6−   ` 0x60 96 140 a 0x61 97 141 b 0x62 98 142 c 0x63 99 143 d 0x64 100 144 e 0x65 101 145 f 0x66 102 146 g 0x67 103 147 h 0x68 104 150 i 0x69 105 151 j 0x6A 106 152 k 0x6B 107 153 l 0x6C 108 154 m 0x6D 109 155 n 0x6E 110 156 o 0x6F 111 157   7−   p 0x70 112 160 q 0x71 113 161 r 0x72 114 162 s 0x73 115 163 t 0x74 116 164 u 0x75 117 165 v 0x76 118 166 w 0x77 119 167 x 0x78 120 170 y 0x79 121 171 z 0x7A 122 172 { 0x7B 123 173 | 0x7C 124 174 } 0x7D 125 175 ~ 0x7E 126 176 _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F 大文字のASCII値に32を加えると小文字に変換することが出来る。この変換は、2進法では、6ビット目に1をセットするだけでよい。また、数字から48を減じれば、対応する値が得られる。この変換は、5ビット目及び6ビット目に0をセットするか、あるいは単純に上位4ビットを無視するだけでもよい。なお、印字可能文字のうち「@」から始まる32文字については、ASCII値を64減じて対応する制御文字を求め、この制御文字を「コントロール+」（英: control+）という前置表現を付けた印字可能文字で表記する慣習がある。 例：BELコード(07) →「コントロール+G」（受信した側の機器で注意喚起音が鳴る） この制御文字の表記方法は、キーボード上の印字可能文字キーを制御文字の送出に用いていた機器の名残りであると考えられる（7ビット目を0にセットする専用キー（Ctrlキー）を、印字可能文字キーと同時に押して制御文字を送出）。 また，Unix 端末では Ctrl+数字 で人間工学的に押下しづらい制御文字を送出できる。具体的には ^2 が ^@，^3 が ^[，^4 が ^\，^5 が ^]，^6 が ^^，^7 が ^_，^8 が ^? であることが多い。 参考文献 「ANSI INCITS 4-1986 (formerly ANSI X3.4-1986) American National Standard for Information Systems ― Coded Character Sets ― 7-Bit American National Standard Code for Information Interchange (7-Bit ASCII)」American National Standards Institute（1963年6月17日制定、1986年3月26日最終改正、2002年1月15日規格番号変更） 関連項目 JIS X 0201 <tbody></tbody> </raw> </toggledisplay> wiki en [Wiki en表示] Not to be confused with MS Windows-1252 or other types of extended ASCII. This article is about the character encoding. For other uses, see ASCII (disambiguation). ASCII ASCII (1967 or later) MIME / IANA us-ascii Alias(es) ASCII Language(s) English Classification ISO 646 series Extensions Unicode ISO 8859 (series) KOI-8 OEM (series) Windows-125x (series) Others Preceded by ITA 2, FIELDATA Succeeded by ISO 8859, Unicode Other related encoding(s) PETSCII ASCII (/ˈæskiː/ (listen) ASS-kee), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Most modern character-encoding schemes are based on ASCII, although they support many additional characters. ASCII is the traditional name for the encoding system; the Internet Assigned Numbers Authority (IANA) prefers the updated name US-ASCII, which clarifies that this system was developed in the US and based on the typographical symbols predominantly in use there. ASCII is one of the IEEE milestones. ASCII chart from an earlier-than 1972 printer manual (b1 is the least significant bit.) Overview ASCII was developed from telegraph code. Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services. Work on the ASCII standard began on October 6, 1960, with the first meeting of the American Standards Association's (ASA) (now the American National Standards Institute or ANSI) X3.2 subcommittee. The first edition of the standard was published in 1963, underwent a major revision during 1967, and experienced its most recent update during 1986. Compared to earlier telegraph codes, the proposed Bell code and ASCII were both ordered for more convenient sorting (i.e., alphabetization) of lists, and added features for devices other than teleprinters. Originally based on the English alphabet, ASCII encodes 128 specified characters into seven-bit integers as shown by the ASCII chart above. Ninety-five of the encoded characters are printable: these include the digits 0 to 9, lowercase letters a to z, uppercase letters A to Z, and punctuation symbols. In addition, the original ASCII specification included 33 non-printing control codes which originated with Teletype machines; most of these are now obsolete, although a few are still commonly used, such as the carriage return, line feed and tab codes. For example, lowercase i would be represented in the ASCII encoding by binary 1101001 = hexadecimal 69 (i is the ninth letter) = decimal 105. History ASCII (1963). Control pictures of equivalent controls are shown where they exist, or a grey dot otherwise. The American Standard Code for Information Interchange (ASCII) was developed under the auspices of a committee of the American Standards Association (ASA), called the X3 committee, by its X3.2 (later X3L2) subcommittee, and later by that subcommittee's X3.2.4 working group (now INCITS). The ASA became the United States of America Standards Institute (USASI) and ultimately the American National Standards Institute (ANSI). With the other special characters and control codes filled in, ASCII was published as ASA X3.4-1963, leaving 28 code positions without any assigned meaning, reserved for future standardization, and one unassigned control code. There was some debate at the time whether there should be more control characters rather than the lowercase alphabet. The indecision did not last long: during May 1963 the CCITT Working Party on the New Telegraph Alphabet proposed to assign lowercase characters to sticks 6 and 7, and International Organization for Standardization TC 97 SC 2 voted during October to incorporate the change into its draft standard. The X3.2.4 task group voted its approval for the change to ASCII at its May 1963 meeting. Locating the lowercase letters in sticks 6 and 7 caused the characters to differ in bit pattern from the upper case by a single bit, which simplified case-insensitive character matching and the construction of keyboards and printers. The X3 committee made other changes, including other new characters (the brace and vertical bar characters), renaming some control characters (SOM became start of header (SOH)) and moving or removing others (RU was removed). ASCII was subsequently updated as USAS X3.4-1967, then USAS X3.4-1968, ANSI X3.4-1977, and finally, ANSI X3.4-1986. Revisions of the ASCII standard: ASA X3.4-1963 ASA X3.4-1965 (approved, but not published, nevertheless used by IBM 2260 & 2265 Display Stations and IBM 2848 Display Control) USAS X3.4-1967 USAS X3.4-1968 ANSI X3.4-1977 ANSI X3.4-1986 ANSI X3.4-1986 (R1992) ANSI X3.4-1986 (R1997) ANSI INCITS 4-1986 (R2002) ANSI INCITS 4-1986 (R2007) ANSI INCITS 4-1986 (R2012) In the X3.15 standard, the X3 committee also addressed how ASCII should be transmitted (least significant bit first), and how it should be recorded on perforated tape. They proposed a 9-track standard for magnetic tape, and attempted to deal with some punched card formats. Design considerations Bit width The X3.2 subcommittee designed ASCII based on the earlier teleprinter encoding systems. Like other character encodings, ASCII specifies a correspondence between digital bit patterns and character symbols (i.e. graphemes and control characters). This allows digital devices to communicate with each other and to process, store, and communicate character-oriented information such as written language. Before ASCII was developed, the encodings in use included 26 alphabetic characters, 10 numerical digits, and from 11 to 25 special graphic symbols. To include all these, and control characters compatible with the Comité Consultatif International Téléphonique et Télégraphique (CCITT) International Telegraph Alphabet No. 2 (ITA2) standard of 1924, FIELDATA (1956), and early EBCDIC (1963), more than 64 codes were required for ASCII. ITA2 were in turn based on the 5-bit telegraph code Émile Baudot invented in 1870 and patented in 1874. The committee debated the possibility of a shift function (like in ITA2), which would allow more than 64 codes to be represented by a six-bit code. In a shifted code, some character codes determine choices between options for the following character codes. It allows compact encoding, but is less reliable for data transmission, as an error in transmitting the shift code typically makes a long part of the transmission unreadable. The standards committee decided against shifting, and so ASCII required at least a seven-bit code. The committee considered an eight-bit code, since eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal. However, it would require all data transmission to send eight bits when seven could suffice. The committee voted to use a seven-bit code to minimize costs associated with data transmission. Since perforated tape at the time could record eight bits in one position, it also allowed for a parity bit for error checking if desired. Eight-bit machines (with octets as the native data type) that did not use parity checking typically set the eighth bit to 0. In some printers, the high bit was used to enable Italics printing. Internal organization The code itself was patterned so that most control codes were together and all graphic codes were together, for ease of identification. The first two so called ASCII sticks (32 positions) were reserved for control characters. The "space" character had to come before graphics to make sorting easier, so it became position 20hex; for the same reason, many special signs commonly used as separators were placed before digits. The committee decided it was important to support uppercase 64-character alphabets, and chose to pattern ASCII so it could be reduced easily to a usable 64-character set of graphic codes, as was done in the DEC SIXBIT code (1963). Lowercase letters were therefore not interleaved with uppercase. To keep options available for lowercase letters and other graphics, the special and numeric codes were arranged before the letters, and the letter A was placed in position 41hex to match the draft of the corresponding British standard. The digits 0–9 are prefixed with 011, but the remaining 4 bits correspond to their respective values in binary, making conversion with binary-coded decimal straightforward. Many of the non-alphanumeric characters were positioned to correspond to their shifted position on typewriters; an important subtlety is that these were based on mechanical typewriters, not electric typewriters. Mechanical typewriters followed the standard set by the Remington No. 2 (1878), the first typewriter with a shift key, and the shifted values of 23456789- were "#$%_&'() – early typewriters omitted 0 and 1, using O (capital letter o) and l (lowercase letter L) instead, but 1! and 0) pairs became standard once 0 and 1 became common. Thus, in ASCII !"#$% were placed in the second stick, positions 1–5, corresponding to the digits 1–5 in the adjacent stick. The parentheses could not correspond to 9 and 0, however, because the place corresponding to 0 was taken by the space character. This was accommodated by removing _ (underscore) from 6 and shifting the remaining characters, which corresponded to many European typewriters that placed the parentheses with 8 and 9. This discrepancy from typewriters led to bit-paired keyboards, notably the Teletype Model 33, which used the left-shifted layout corresponding to ASCII, not to traditional mechanical typewriters. Electric typewriters, notably the IBM Selectric (1961), used a somewhat different layout that has become standard on computers – following the IBM PC (1981), especially Model M (1984) – and thus shift values for symbols on modern keyboards do not correspond as closely to the ASCII table as earlier keyboards did. The /? pair also dates to the No. 2, and the ,< .> pairs were used on some keyboards (others, including the No. 2, did not shift , (comma) or . (full stop) so they could be used in uppercase without unshifting). However, ASCII split the ;: pair (dating to No. 2), and rearranged mathematical symbols (varied conventions, commonly -* =+) to :* ;+ -=. Some common characters were not included, notably ½¼¢, while ^`~ were included as diacritics for international use, and <> for mathematical use, together with the simple line characters \| (in addition to common /). The @ symbol was not used in continental Europe and the committee expected it would be replaced by an accented À in the French variation, so the @ was placed in position 40hex, right before the letter A. The control codes felt essential for data transmission were the start of message (SOM), end of address (EOA), end of message (EOM), end of transmission (EOT), "who are you?" (WRU), "are you?" (RU), a reserved device control (DC0), synchronous idle (SYNC), and acknowledge (ACK). These were positioned to maximize the Hamming distance between their bit patterns. Character order ASCII-code order is also called ASCIIbetical order. Collation of data is sometimes done in this order rather than "standard" alphabetical order (collating sequence). The main deviations in ASCII order are: All uppercase come before lowercase letters; for example, "Z" precedes "a" Digits and many punctuation marks come before letters An intermediate order converts uppercase letters to lowercase before comparing ASCII values. Character groups Control characters Main article: Control character ASCII reserves the first 32 codes (numbers 0–31 decimal) for control characters: codes originally intended not to represent printable information, but rather to control devices (such as printers) that make use of ASCII, or to provide meta-information about data streams such as those stored on magnetic tape. For example, character 10 represents the "line feed" function (which causes a printer to advance its paper), and character 8 represents "backspace". RFC 2822 refers to control characters that do not include carriage return, line feed or white space as non-whitespace control characters. Except for the control characters that prescribe elementary line-oriented formatting, ASCII does not define any mechanism for describing the structure or appearance of text within a document. Other schemes, such as markup languages, address page and document layout and formatting. The original ASCII standard used only short descriptive phrases for each control character. The ambiguity this caused was sometimes intentional, for example where a character would be used slightly differently on a terminal link than on a data stream, and sometimes accidental, for example with the meaning of "delete". Probably the most influential single device on the interpretation of these characters was the Teletype Model 33 ASR, which was a printing terminal with an available paper tape reader/punch option. Paper tape was a very popular medium for long-term program storage until the 1980s, less costly and in some ways less fragile than magnetic tape. In particular, the Teletype Model 33 machine assignments for codes 17 (Control-Q, DC1, also known as XON), 19 (Control-S, DC3, also known as XOFF), and 127 (Delete) became de facto standards. The Model 33 was also notable for taking the description of Control-G (code 7, BEL, meaning audibly alert the operator) literally, as the unit contained an actual bell which it rang when it received a BEL character. Because the keytop for the O key also showed a left-arrow symbol (from ASCII-1963, which had this character instead of underscore), a noncompliant use of code 15 (Control-O, Shift In) interpreted as "delete previous character" was also adopted by many early timesharing systems but eventually became neglected. When a Teletype 33 ASR equipped with the automatic paper tape reader received a Control-S (XOFF, an abbreviation for transmit off), it caused the tape reader to stop; receiving Control-Q (XON, "transmit on") caused the tape reader to resume. This technique became adopted by several early computer operating systems as a "handshaking" signal warning a sender to stop transmission because of impending overflow; it persists to this day in many systems as a manual output control technique. On some systems Control-S retains its meaning but Control-Q is replaced by a second Control-S to resume output. The 33 ASR also could be configured to employ Control-R (DC2) and Control-T (DC4) to start and stop the tape punch; on some units equipped with this function, the corresponding control character lettering on the keycap above the letter was TAPE and TAPE respectively. The Teletype could not move the head backwards, so it did not put a key on the keyboard to send a BS (backspace). Instead there was a key marked "rubout" that sent code 127 (DEL). The purpose of this key was to erase mistakes in a hand-typed paper tape: the operator had to push a button on the tape punch to back it up, then type the rubout, which punched all holes and replaced the mistake with a character that was intended to be ignored. Teletypes were commonly used for the less-expensive computers from Digital Equipment Corporation, so these systems had to use the available key and thus the DEL code to erase the previous character. Because of this, DEC video terminals (by default) sent the DEL code for the key marked "Backspace" while the key marked "Delete" sent an escape sequence, while many other terminals sent BS for the Backspace key. The Unix terminal driver could only use one code to back up, this could be set to BS or DEL, but not both, resulting in a very long period of annoyance where you had to correct it depending on what terminal you were using (modern shells using readline understand both codes). The assumption that no key sent a BS caused Control+H to be used for other purposes, such as a "help" command in Emacs. Many more of the control codes have been given meanings quite different from their original ones. The "escape" character (ESC, code 27), for example, was intended originally to allow sending other control characters as literals instead of invoking their meaning. This is the same meaning of "escape" encountered in URL encodings, C language strings, and other systems where certain characters have a reserved meaning. Over time this meaning has been co-opted and has eventually been changed. In modern use, an ESC sent to the terminal usually indicates the start of a command sequence usually in the form of a so-called "ANSI escape code" (or, more properly, a "Control Sequence Introducer") from ECMA-48 (1972) and its successors, beginning with ESC followed by a "[" (left-bracket) character. An ESC sent from the terminal is most often used as an out-of-band character used to terminate an operation, as in the TECO and vi text editors. In graphical user interface (GUI) and windowing systems, ESC generally causes an application to abort its current operation or to exit (terminate) altogether. The inherent ambiguity of many control characters, combined with their historical usage, created problems when transferring "plain text" files between systems. The best example of this is the newline problem on various operating systems. Teletype machines required that a line of text be terminated with both "Carriage Return" (which moves the printhead to the beginning of the line) and "Line Feed" (which advances the paper one line without moving the printhead). The name "Carriage Return" comes from the fact that on a manual typewriter the carriage holding the paper moved while the position where the typebars struck the ribbon remained stationary. The entire carriage had to be pushed (returned) to the right in order to position the left margin of the paper for the next line. DEC operating systems (OS/8, RT-11, RSX-11, RSTS, TOPS-10, etc.) used both characters to mark the end of a line so that the console device (originally Teletype machines) would work. By the time so-called "glass TTYs" (later called CRTs or terminals) came along, the convention was so well established that backward compatibility necessitated continuing the convention. When Gary Kildall created CP/M he was inspired by some command line interface conventions used in DEC's RT-11. Until the introduction of PC DOS in 1981, IBM had no hand in this because their 1970s operating systems used EBCDIC instead of ASCII and they were oriented toward punch-card input and line printer output on which the concept of carriage return was meaningless. IBM's PC DOS (also marketed as MS-DOS by Microsoft) inherited the convention by virtue of being loosely based on CP/M, and Windows inherited it from MS-DOS. Unfortunately, requiring two characters to mark the end of a line introduces unnecessary complexity and questions as to how to interpret each character when encountered alone. To simplify matters plain text data streams, including files, on Multics used line feed (LF) alone as a line terminator. Unix and Unix-like systems, and Amiga systems, adopted this convention from Multics. The original Macintosh OS, Apple DOS, and ProDOS, on the other hand, used carriage return (CR) alone as a line terminator; however, since Apple replaced these operating systems with the Unix-based macOS operating system, they now use line feed (LF) as well. The Radio Shack TRS-80 also used a lone CR to terminate lines. Computers attached to the ARPANET included machines running operating systems such as TOPS-10 and TENEX using CR-LF line endings, machines running operating systems such as Multics using LF line endings, and machines running operating systems such as OS/360 that represented lines as a character count followed by the characters of the line and that used EBCDIC rather than ASCII. The Telnet protocol defined an ASCII "Network Virtual Terminal" (NVT), so that connections between hosts with different line-ending conventions and character sets could be supported by transmitting a standard text format over the network. Telnet used ASCII along with CR-LF line endings, and software using other conventions would translate between the local conventions and the NVT. The File Transfer Protocol adopted the Telnet protocol, including use of the Network Virtual Terminal, for use when transmitting commands and transferring data in the default ASCII mode. This adds complexity to implementations of those protocols, and to other network protocols, such as those used for E-mail and the World Wide Web, on systems not using the NVT's CR-LF line-ending convention. The PDP-6 monitor, and its PDP-10 successor TOPS-10, used Control-Z (SUB) as an end-of-file indication for input from a terminal. Some operating systems such as CP/M tracked file length only in units of disk blocks and used Control-Z to mark the end of the actual text in the file. For these reasons, EOF, or end-of-file, was used colloquially and conventionally as a three-letter acronym for Control-Z instead of SUBstitute. The end-of-text code (ETX), also known as Control-C, was inappropriate for a variety of reasons, while using Z as the control code to end a file is analogous to it ending the alphabet and serves as a very convenient mnemonic aid. A historically common and still prevalent convention uses the ETX code convention to interrupt and halt a program via an input data stream, usually from a keyboard. In C library and Unix conventions, the null character is used to terminate text strings; such null-terminated strings can be known in abbreviation as ASCIZ or ASCIIZ, where here Z stands for "zero". Binary Oct Dec Hex Abbreviation Name (1967) 1963 1965 1967 000 0000 000 0 00 NULL NUL ␀ ^@ Null 000 0001 001 1 01 SOM SOH ␁ ^A Start of Heading 000 0010 002 2 02 EOA STX ␂ ^B Start of Text 000 0011 003 3 03 EOM ETX ␃ ^C End of Text 000 0100 004 4 04 EOT ␄ ^D End of Transmission 000 0101 005 5 05 WRU ENQ ␅ ^E Enquiry 000 0110 006 6 06 RU ACK ␆ ^F Acknowledgement 000 0111 007 7 07 BELL BEL ␇ ^G \a Bell 000 1000 010 8 08 FE0 BS ␈ ^H \b Backspace 000 1001 011 9 09 HT/SK HT ␉ ^I \t Horizontal Tab 000 1010 012 10 0A LF ␊ ^J \n Line Feed 000 1011 013 11 0B VTAB VT ␋ ^K \v Vertical Tab 000 1100 014 12 0C FF ␌ ^L \f Form Feed 000 1101 015 13 0D CR ␍ ^M \r Carriage Return 000 1110 016 14 0E SO ␎ ^N Shift Out 000 1111 017 15 0F SI ␏ ^O Shift In 001 0000 020 16 10 DC0 DLE ␐ ^P Data Link Escape 001 0001 021 17 11 DC1 ␑ ^Q Device Control 1 (often XON) 001 0010 022 18 12 DC2 ␒ ^R Device Control 2 001 0011 023 19 13 DC3 ␓ ^S Device Control 3 (often XOFF) 001 0100 024 20 14 DC4 ␔ ^T Device Control 4 001 0101 025 21 15 ERR NAK ␕ ^U Negative Acknowledgement 001 0110 026 22 16 SYNC SYN ␖ ^V Synchronous Idle 001 0111 027 23 17 LEM ETB ␗ ^W End of Transmission Block 001 1000 030 24 18 S0 CAN ␘ ^X Cancel 001 1001 031 25 19 S1 EM ␙ ^Y End of Medium 001 1010 032 26 1A S2 SS SUB ␚ ^Z Substitute 001 1011 033 27 1B S3 ESC ␛ ^[ \e Escape 001 1100 034 28 1C S4 FS ␜ ^\ File Separator 001 1101 035 29 1D S5 GS ␝ ^] Group Separator 001 1110 036 30 1E S6 RS ␞ ^^ Record Separator 001 1111 037 31 1F S7 US ␟ ^_ Unit Separator 111 1111 177 127 7F DEL ␡ ^? Delete Other representations might be used by specialist equipment, for example ISO 2047 graphics or hexadecimal numbers. Printable characters Codes 20hex to 7Ehex, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. There are 95 printable characters in total. Code 20hex, the "space" character, denotes the space between words, as produced by the space bar of a keyboard. Since the space character is considered an invisible graphic (rather than a control character) it is listed in the table below instead of in the previous section. Code 7Fhex corresponds to the non-printable "delete" (DEL) control character and is therefore omitted from this chart; it is covered in the previous section's chart. Earlier versions of ASCII used the up arrow instead of the caret (5Ehex) and the left arrow instead of the underscore (5Fhex). Binary Oct Dec Hex Glyph 1963 1965 1967 010 0000 040 32 20  space 010 0001 041 33 21 ! 010 0010 042 34 22 " 010 0011 043 35 23 # 010 0100 044 36 24 $ 010 0101 045 37 25 % 010 0110 046 38 26 & 010 0111 047 39 27 ' 010 1000 050 40 28 ( 010 1001 051 41 29 ) 010 1010 052 42 2A * 010 1011 053 43 2B + 010 1100 054 44 2C , 010 1101 055 45 2D - 010 1110 056 46 2E . 010 1111 057 47 2F / 011 0000 060 48 30 0 011 0001 061 49 31 1 011 0010 062 50 32 2 011 0011 063 51 33 3 011 0100 064 52 34 4 011 0101 065 53 35 5 011 0110 066 54 36 6 011 0111 067 55 37 7 011 1000 070 56 38 8 011 1001 071 57 39 9 011 1010 072 58 3A : 011 1011 073 59 3B ; 011 1100 074 60 3C < 011 1101 075 61 3D = 011 1110 076 62 3E > 011 1111 077 63 3F ? 100 0000 100 64 40 @ ` @ 100 0001 101 65 41 A 100 0010 102 66 42 B 100 0011 103 67 43 C 100 0100 104 68 44 D 100 0101 105 69 45 E 100 0110 106 70 46 F 100 0111 107 71 47 G 100 1000 110 72 48 H 100 1001 111 73 49 I 100 1010 112 74 4A J 100 1011 113 75 4B K 100 1100 114 76 4C L 100 1101 115 77 4D M 100 1110 116 78 4E N 100 1111 117 79 4F O 101 0000 120 80 50 P 101 0001 121 81 51 Q 101 0010 122 82 52 R 101 0011 123 83 53 S 101 0100 124 84 54 T 101 0101 125 85 55 U 101 0110 126 86 56 V 101 0111 127 87 57 W 101 1000 130 88 58 X 101 1001 131 89 59 Y 101 1010 132 90 5A Z 101 1011 133 91 5B [ 101 1100 134 92 5C \ ~ \ 101 1101 135 93 5D ] 101 1110 136 94 5E ↑ ^ 101 1111 137 95 5F ← _ 110 0000 140 96 60 @ ` 110 0001 141 97 61 a 110 0010 142 98 62 b 110 0011 143 99 63 c 110 0100 144 100 64 d 110 0101 145 101 65 e 110 0110 146 102 66 f 110 0111 147 103 67 g 110 1000 150 104 68 h 110 1001 151 105 69 i 110 1010 152 106 6A j 110 1011 153 107 6B k 110 1100 154 108 6C l 110 1101 155 109 6D m 110 1110 156 110 6E n 110 1111 157 111 6F o 111 0000 160 112 70 p 111 0001 161 113 71 q 111 0010 162 114 72 r 111 0011 163 115 73 s 111 0100 164 116 74 t 111 0101 165 117 75 u 111 0110 166 118 76 v 111 0111 167 119 77 w 111 1000 170 120 78 x 111 1001 171 121 79 y 111 1010 172 122 7A z 111 1011 173 123 7B { 111 1100 174 124 7C ACK ¬ | 111 1101 175 125 7D } 111 1110 176 126 7E ESC | ~ Character set ASCII (1977/1986) _0 _1 _2 _3 _4 _5 _6 _7 _8 _9 _A _B _C _D _E _F 0_ 0 NUL 0000 SOH 0001 STX 0002 ETX 0003 EOT 0004 ENQ 0005 ACK 0006 BEL 0007 BS 0008 HT 0009 LF 000A VT 000B FF 000C CR 000D SO 000E SI 000F 1_ 16 DLE 0010 DC1 0011 DC2 0012 DC3 0013 DC4 0014 NAK 0015 SYN 0016 ETB 0017 CAN 0018 EM 0019 SUB 001A ESC 001B FS 001C GS 001D RS 001E US 001F 2_ 32 SP 0020 ! 0021 " 0022 # 0023 $ 0024 % 0025 & 0026 ' 0027 ( 0028 ) 0029 * 002A + 002B , 002C - 002D . 002E / 002F 3_ 48 0 0030 1 0031 2 0032 3 0033 4 0034 5 0035 6 0036 7 0037 8 0038 9 0039 : 003A ; 003B < 003C = 003D > 003E ? 003F 4_ 64 @ 0040 A 0041 B 0042 C 0043 D 0044 E 0045 F 0046 G 0047 H 0048 I 0049 J 004A K 004B L 004C M 004D N 004E O 004F 5_ 80 P 0050 Q 0051 R 0052 S 0053 T 0054 U 0055 V 0056 W 0057 X 0058 Y 0059 Z 005A [ 005B \ 005C ] 005D ^ 005E _ 005F 6_ 96 ` 0060 a 0061 b 0062 c 0063 d 0064 e 0065 f 0066 g 0067 h 0068 i 0069 j 006A k 006B l 006C m 006D n 006E o 006F 7_ 112 p 0070 q 0071 r 0072 s 0073 t 0074 u 0075 v 0076 w 0077 x 0078 y 0079 z 007A { 007B | 007C } 007D ~ 007E DEL 007F   Letter   Number   Punctuation   Symbol   Other   undefined   Changed from 1963 version Use ASCII was first used commercially during 1963 as a seven-bit teleprinter code for American Telephone & Telegraph's TWX (TeletypeWriter eXchange) network. TWX originally used the earlier five-bit ITA2, which was also used by the competing Telex teleprinter system. Bob Bemer introduced features such as the escape sequence. His British colleague Hugh McGregor Ross helped to popularize this work – according to Bemer, "so much so that the code that was to become ASCII was first called the Bemer–Ross Code in Europe". Because of his extensive work on ASCII, Bemer has been called "the father of ASCII". On March 11, 1968, U.S. President Lyndon B. Johnson mandated that all computers purchased by the United States Federal Government support ASCII, stating: I have also approved recommendations of the Secretary of Commerce [Luther H. Hodges] regarding standards for recording the Standard Code for Information Interchange on magnetic tapes and paper tapes when they are used in computer operations. All computers and related equipment configurations brought into the Federal Government inventory on and after July 1, 1969, must have the capability to use the Standard Code for Information Interchange and the formats prescribed by the magnetic tape and paper tape standards when these media are used. ASCII was the most common character encoding on the World Wide Web until December 2007, when UTF-8 encoding surpassed it; UTF-8 is backward compatible with ASCII. Variants and derivations As computer technology spread throughout the world, different standards bodies and corporations developed many variations of ASCII to facilitate the expression of non-English languages that used Roman-based alphabets. One could class some of these variations as "ASCII extensions", although some misuse that term to represent all variants, including those that do not preserve ASCII's character-map in the 7-bit range. Furthermore, the ASCII extensions have also been mislabelled as ASCII. 7-bit codes Main articles: ECMA-6, ISO/IEC 646, and ITU T.50 See also: UTF-7 From early in its development, ASCII was intended to be just one of several national variants of an international character code standard. Other international standards bodies have ratified character encodings such as ISO 646 (1967) that are identical or nearly identical to ASCII, with extensions for characters outside the English alphabet and symbols used outside the United States, such as the symbol for the United Kingdom's pound sterling (£). Almost every country needed an adapted version of ASCII, since ASCII suited the needs of only the US and a few other countries. For example, Canada had its own version that supported French characters. Many other countries developed variants of ASCII to include non-English letters (e.g. é, ñ, ß, Ł), currency symbols (e.g. £, ¥), etc. See also YUSCII (Yugoslavia). It would share most characters in common, but assign other locally useful characters to several code points reserved for "national use". However, the four years that elapsed between the publication of ASCII-1963 and ISO's first acceptance of an international recommendation during 1967 caused ASCII's choices for the national use characters to seem to be de facto standards for the world, causing confusion and incompatibility once other countries did begin to make their own assignments to these code points. ISO/IEC 646, like ASCII, is a 7-bit character set. It does not make any additional codes available, so the same code points encoded different characters in different countries. Escape codes were defined to indicate which national variant applied to a piece of text, but they were rarely used, so it was often impossible to know what variant to work with and, therefore, which character a code represented, and in general, text-processing systems could cope with only one variant anyway. Because the bracket and brace characters of ASCII were assigned to "national use" code points that were used for accented letters in other national variants of ISO/IEC 646, a German, French, or Swedish, etc. programmer using their national variant of ISO/IEC 646, rather than ASCII, had to write, and thus read, something such as ä aÄiÜ = 'Ön'; ü instead of { a[i] = '\n'; } C trigraphs were created to solve this problem for ANSI C, although their late introduction and inconsistent implementation in compilers limited their use. Many programmers kept their computers on US-ASCII, so plain-text in Swedish, German etc. (for example, in e-mail or Usenet) contained "{, }" and similar variants in the middle of words, something those programmers got used to. For example, a Swedish programmer mailing another programmer asking if they should go for lunch, could get "N{ jag har sm|rg}sar" as the answer, which should be "Nä jag har smörgåsar" meaning "No I've got sandwiches". 8-bit codes Main articles: Extended ASCII and ISO/IEC 8859 See also: UTF-8 Eventually, as 8-, 16- and 32-bit (and later 64-bit) computers began to replace 12-, 18- and 36-bit computers as the norm, it became common to use an 8-bit byte to store each character in memory, providing an opportunity for extended, 8-bit relatives of ASCII. In most cases these developed as true extensions of ASCII, leaving the original character-mapping intact, but adding additional character definitions after the first 128 (i.e., 7-bit) characters. Encodings include ISCII (India), VISCII (Vietnam). Although these encodings are sometimes referred to as ASCII, true ASCII is defined strictly only by the ANSI standard. Most early home computer systems developed their own 8-bit character sets containing line-drawing and game glyphs, and often filled in some or all of the control characters from 0 to 31 with more graphics. Kaypro CP/M computers used the "upper" 128 characters for the Greek alphabet. The PETSCII code Commodore International used for their 8-bit systems is probably unique among post-1970 codes in being based on ASCII-1963, instead of the more common ASCII-1967, such as found on the ZX Spectrum computer. Atari 8-bit computers and Galaksija computers also used ASCII variants. The IBM PC defined code page 437, which replaced the control characters with graphic symbols such as smiley faces, and mapped additional graphic characters to the upper 128 positions. Operating systems such as DOS supported these code pages, and manufacturers of IBM PCs supported them in hardware. Digital Equipment Corporation developed the Multinational Character Set (DEC-MCS) for use in the popular VT220 terminal as one of the first extensions designed more for international languages than for block graphics. The Macintosh defined Mac OS Roman and Postscript also defined a set, both of these contained both international letters and typographic punctuation marks instead of graphics, more like modern character sets. The ISO/IEC 8859 standard (derived from the DEC-MCS) finally provided a standard that most systems copied (at least as accurately as they copied ASCII, but with many substitutions). A popular further extension designed by Microsoft, Windows-1252 (often mislabeled as ISO-8859-1), added the typographic punctuation marks needed for traditional text printing. ISO-8859-1, Windows-1252, and the original 7-bit ASCII were the most common character encodings until 2008 when UTF-8 became more common. ISO/IEC 4873 introduced 32 additional control codes defined in the 80–9F hexadecimal range, as part of extending the 7-bit ASCII encoding to become an 8-bit system. Unicode Main articles: Unicode and ISO/IEC 10646 See also: Basic Latin (Unicode block) Unicode and the ISO/IEC 10646 Universal Character Set (UCS) have a much wider array of characters and their various encoding forms have begun to supplant ISO/IEC 8859 and ASCII rapidly in many environments. While ASCII is limited to 128 characters, Unicode and the UCS support more characters by separating the concepts of unique identification (using natural numbers called code points) and encoding (to 8-, 16- or 32-bit binary formats, called UTF-8, UTF-16 and UTF-32). ASCII was incorporated into the Unicode (1991) character set as the first 128 symbols, so the 7-bit ASCII characters have the same numeric codes in both sets. This allows UTF-8 to be backward compatible with 7-bit ASCII, as a UTF-8 file containing only ASCII characters is identical to an ASCII file containing the same sequence of characters. Even more importantly, forward compatibility is ensured as software that recognizes only 7-bit ASCII characters as special and does not alter bytes with the highest bit set (as is often done to support 8-bit ASCII extensions such as ISO-8859-1) will preserve UTF-8 data unchanged. See also 3568 ASCII, an asteroid named after the character encoding Ascii85 ASCII art ASCII Ribbon Campaign Basic Latin (Unicode block) (ASCII as a subset of Unicode) Extended ASCII HTML decimal character rendering List of Unicode characters Jargon File, a glossary of computer programmer slang which includes a list of common slang names for ASCII characters List of computer character sets Alt codes Further reading Bemer, Robert William (1960). "A Proposal for Character Code Compatibility". Communications of the ACM. 3 (2): 71–72. doi:10.1145/366959.366961. Bemer, Robert William (2003-05-23). "The Babel of Codes Prior to ASCII: The 1960 Survey of Coded Character Sets: The Reasons for ASCII". Archived from the original on 2013-10-17. Retrieved 2016-05-09, from: Bemer, Robert William (December 1960). "Survey of coded character representation". Communications of the ACM. 3 (12): 639–641. doi:10.1145/367487.367493. Smith, H. J.; Williams, F. A. (December 1960). "Survey of punched card codes". Communications of the ACM. 3 (12): 642. doi:10.1145/367487.367491. American National Standard Code for Information Interchange. American National Standards Institute. 1977. Robinson, G. S.; Cargill, C. (1996). "History and impact of computer standards". Computer. 29 (10): 79–85. doi:10.1109/2.539725. Mullendore, Ralph Elvin (1964) [1963]. Ptak, John F., ed. "On the Early Development of ASCII – The History of ASCII". JF Ptak Science Books (published March 2012). Archived from the original on 2016-05-26. Retrieved 2016-05-26. External links "C0 Controls and Basic Latin – Range: 0000–007F" (PDF). The Unicode Standard 8.0. Unicode, Inc. 2015 [1991]. Archived (PDF) from the original on 2016-05-26. Retrieved 2016-05-26. Fischer, Eric. "The Evolution of Character Codes, 1874–1968". Retrieved 2016-05-26. [1] English Journal A combined application of lossless and lossy compression in ECG processing and transmission via GSM-based SMS. Mukhopadhyay SK1, Mitra S, Mitra M. Journal of medical engineering & technology.J Med Eng Technol.2015 Feb;39(2):105-22. doi: 10.3109/03091902.2014.990159. Epub 2014 Dec 23. PMID 25534118 A practical data processing workflow for multi-OMICS projects. Kohl M1, Megger DA, Trippler M, Meckel H, Ahrens M, Bracht T, Weber F, Hoffmann AC, Baba HA, Sitek B, Schlaak JF, Meyer HE, Stephan C, Eisenacher M. Biochimica et biophysica acta.Biochim Biophys Acta.2014 Jan;1844(1 Pt A):52-62. doi: 10.1016/j.bbapap.2013.02.029. Epub 2013 Mar 15. PMID 23501674 Controlled vocabularies and ontologies in proteomics: overview, principles and practice. Mayer G1, Jones AR, Binz PA, Deutsch EW, Orchard S, Montecchi-Palazzi L, Vizcaíno JA, Hermjakob H, Oveillero D, Julian R, Stephan C, Meyer HE, Eisenacher M. Biochimica et biophysica acta.Biochim Biophys Acta.2014 Jan;1844(1 Pt A):98-107. doi: 10.1016/j.bbapap.2013.02.017. Epub 2013 Feb 19. PMID 23429179 Japanese Journal Proposed revised American standard code for information interchange GORN S. Communications of the ACM 8(4), 207-214, 1965 NAID 30022110337 New American standard code for information interchange SMITH F. W. Western Union Technical Review 18(2), 50-61, 1964 NAID 10011806098 American standard code for information interchange GORN S. Communications of the ACM 6(8), 422-426, 1963 NAID 30022112693 ★リンクテーブル★ リンク元 「アスキー・コード」「情報交換用米国標準コード」 関連記事 「standard」「information」「code」「interchange」「American」 「アスキー・コード」 　　[★] 英 ASCII Code 同 情報交換用米国標準コード American Standard Code for Information Interchange, ASCII 「情報交換用米国標準コード」 　　[★] American Standard Code for Information Interchange, ASCII。アスキー・コード 「standard」 　　[★] n. 標準、基準、スタンダード、規格 adj. 標準物質、標準的な 関 authentic、bench mark、benchmark、calibrator、canonical、criteria、criterion、level、measure、norm、reference、reference standard、specification、standard preparation、standardization 　 　 　 　 　 　 　 　 　 　 　 「information」 　　[★] n. 情報、通知、案内 関 guide、inform、informational、notice、notification 　 　 　 　 　 「code」 　　[★] n. コード、規範、番号 v. コードする 関 cord、paradigm 　 　 　 　 　 　 「interchange」 　　[★] n. 交換 v. 交換する 関 exchange、replace、replacement、swap 　 　 　 　 「American」 　　[★] アメリカの、アメリカ人 関 America