ASCII (American Standard Code for Information Interchange), generally pronounced [ˈæski], is a character encoding based on the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that work with text. Most modern character encodings — which support many more characters — have a historical basis in ASCII. This chart shows concisely the most common way in which the International Phonetic Alphabet (IPA) is applied to represent the English language. ... A character encoding or character set (sometimes referred to as code page) consists of a code that pairs a sequence of characters from a given set with something else, such as a sequence of natural numbers, octets or electrical pulses, in order to facilitate the storage of text in computers... The modern English alphabet consists of the 26 letters[1] of the Latin alphabet: The exact shape of printed letters varies depending on the typeface. ... In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme or a grapheme-like unit or symbol, such as in an alphabet or syllabary in the written form of a natural language. ... A BlueGene supercomputer cabinet. ... Telecommunication involves the transmission of signals over a distance for the purpose of communication. ... A character encoding or character set (sometimes referred to as code page) consists of a code that pairs a sequence of characters from a given set with something else, such as a sequence of natural numbers, octets or electrical pulses, in order to facilitate the storage of text in computers...

Work on ASCII started yesterday. The first edition of the standard was published in 1963,^[1] a major revision in 1967, and the most recent update in 1986. It currently defines codes for 128 characters: 33 are non-printing, mostly obsolete control characters that affect how text is processed, and 95 are printable characters. In computing, a control character or non-printing character, is a code point (a number) in a character set that does not in itself represent a written symbol. ...

Overview

Like other character representation computer codes, ASCII specifies a correspondence between digital bit patterns and the glyphs (i.e., symbols) of a written language. This allows digital devices to communicate with each other and to process, store, and communicate character-oriented information. The ASCII character encoding^[2] —or a compatible extension (see below)—is used on nearly all common computers, especially personal computers and workstations. The preferred MIME name for this encoding is "US-ASCII".^[3] In communications, a code is a rule for converting a piece of information (for example, a letter, word, or phrase) into another form or representation, not necessarily of the same type. ... variant glyphs representing the character a (allographs of a) in the Zapfino typeface. ... A digital system is one that uses discrete values (often electrical voltages), especially those representable as binary numbers, or non-numeric symbols such as letters or icons, for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (ie, as in an analog system). ... Sun SPARCstation 1+, 25mhz RISC processor from early 1990s A workstation, such as a Unix workstation, RISC workstation or engineering workstation, is a high-end desktop or deskside microcomputer designed for technical applications. ... Multipurpose Internet Mail Extensions (MIME) is an Internet Standard that extends the format of e-mail to support: text in character sets other than US-ASCII; non-text attachments; multi-part message bodies; and header information in non-ASCII character sets. ...

Except for a few of the ASCII control characters that prescribe some 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. A specialized markup language using SGML is used to write the electronic version of the Oxford English Dictionary. ...

ASCII is, strictly, a seven-bit code, meaning it uses patterns of seven binary digits (a range of 0 to 127 decimal) to represent each character. When ASCII was introduced, many computers used eight-bit bytes (groups of bits), called octets, as the smallest unit of information. In seven-bit ASCII encoding, the eighth bit was commonly used as a parity bit for error checking on communication lines or for other device-specific functions. Machines that did not use parity checking typically set the eighth bit to 0.^[4] This article is about the unit of information. ... In computer science a byte is a unit of measurement of information storage, most often consisting of eight bits. ... In computer technology and networking, an octet is a group of 8 bits. ... A parity bit is a binary digit that indicates whether the number of bits with value of one in a given set of bits is even or odd. ...

The American National Standards Institute (then called the United States of America Standards Institute or USASI) developed ASCII based on earlier teleprinter encoding systems. ASCII itself first entered commercial use in 1963 as a seven-bit teleprinter code for American Telephone & Telegraph's TWX (Teletype Wide-area eXchange) network. TWX originally used the earlier five-bit Baudot code, which was also used by the competing Telex teleprinter system. The Bell System had planned to upgrade to a six-bit code derived from the Fieldata project, which added punctuation and lower-case letters to the Baudot code, but was persuaded instead to join the American Standards Association (part of ANSI) subcommittee that had started to develop ASCII.^{[citation needed]} Compared with earlier telegraph codes, the proposed Bell code and ASCII both underwent re-ordering for more convenient sorting (especially alphabetization) of lists, and added features for devices other than teleprinters. Bob Bemer introduced features such as the escape sequence.^{[citation needed]} 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".^{[citation needed]} The American National Standards Institute or ANSI (pronounced an-see) is a nonprofit organization that oversees the development of standards for products, services, processes and systems in the United States. ... Teletype machines in World War II A teleprinter (teletypewriter, teletype or TTY for TeleTYpe/TeleTYpewriter) is a now largely obsolete electro-mechanical typewriter which can be used to communicate typed messages from point to point through a simple electrical communications channel, often just a pair of wires. ... AT&T (formerly an abbreviation for American Telephone and Telegraph) Corporation (NYSE: T) is an American telecommunications company. ... Telegraphy (from the Greek words tele = far away and grapho = write) is the long distance transmission of written messages without physical transport of letters, originally over wire. ... The Baudot code, named after its inventor Émile Baudot, is a character set predating EBCDIC and ASCII and used originally and primarily on teleprinters. ... Telex can refer to more than one thing: For the communications network, see Telegraphy. ... Fieldata was a pioneering computer project run by the US Army Signal Corps in the late 1950s that intended to create a single standard for collecting and distributing battlefield information. ... The American National Standards Institute or ANSI (pronounced an-see) is a nonprofit organization that oversees the development of standards for products, services, processes and systems in the United States. ...

ASCII was subsequently updated and published as USASI X3.4-1968, ANSI X3.4-1977, and finally, ANSI X3.4-1986.

Other international standards bodies have ratified character encodings such as ISO 646 that are identical or nearly identical to ASCII, with extensions for characters outside the English alphabet and symbols used outside the Unites States, such as the symbol for the United Kingdom's pound sterling (£). Although these encodings are sometimes referred to as ASCII, true ASCII is strictly defined only by ANSI standard. ISO 646 is an ISO standard that specifies a 7 bit character code from which several national standards are derived, the best known of which is ASCII. Since the portion of ISO 646 shared by all countries specified only the letters used in the English alphabet, other countries using the... The modern English alphabet consists of the 26 letters[1] of the Latin alphabet: The exact shape of printed letters varies depending on the typeface. ... ISO 4217 Code GBP User(s) United Kingdom, Crown Dependencies Inflation 2. ...

ASCII is embedded in its apparent replacement, Unicode, as the lowest 128 characters. Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ...

ASCII control characters

ASCII reserves the first 32 codes (numbers 0–31 decimal) for control characters: codes originally intended not to carry 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". In computing, a control character or non-printing character, is a code point (a number) in a character set that does not in itself represent a written symbol. ... This does not cite any references or sources. ...

The original ASCII standard used only short descriptive phrases for each control character. The ambiguity this left was sometimes intentional (where a character would be used slightly differently on a terminal link than on a data stream) and sometimes more accidental (such as what "delete" means). The null character (also null terminator) is a character with the value zero, present in the ASCII and Unicode character sets, and available in nearly all mainstream programming languages. ... Thenull character (also null terminator) is a character with the value zero, present in the ASCII and Unicode character sets, and available in nearly all mainstream programming languages. ... In computing, control-C is a control character in ASCII code. ... In telecommunication, an end-of-transmission character (EOT) is a transmission control character used to indicate the conclusion of a transmission that may have included one or more texts and any associated message headings. ... In telecommunication, an end-of-transmission character (EOT) is a transmission control character used to indicate the conclusion of a transmission that may have included one or more texts and any associated message headings. ... Acknowledge character (ACK): A transmission control character transmitted by the receiving station as an affirmative response to the sending station. ... Bell character is an ASCII control character, code 7 (^G). ... Bell character is an ASCII control character, code 7 (^G). ... Backspace is the keyboard key that originally pushed the typewriter head one position backwards, and in modern computer displays moves the cursor one position backwards and deletes the preceding character. ... Backspace is the keyboard key that originally pushed the typewriter head one position backwards, and in modern computer displays moves the cursor one position backwards and deletes the preceding character. ... This article is about the use of the term Tab in computing. ... This article is about the use of the term Tab in computing. ... In computing, line feed (LF) is a control character indicating that one line should be fed out. ... In computing, line feed (LF) is a control character indicating that one line should be fed out. ... In computing, form feed is one of control characters in ASCII.  It forces the printer to eject the current page and to continue printing at the top of another. ... Originally, carriage return was the term for the key, lever, or mechanism on a typewriter that would cause the cylinder on which the paper was held (the carriage) to return to the left side of the paper after a line of text had been typed, and would often move it... Originally, carriage return was the term for the key, lever, or mechanism on a typewriter that would cause the cylinder on which the paper was held (the carriage) to return to the left side of the paper after a line of text had been typed, and would often move it... Shift Out (SO) and Shift In (SI) are ASCII control characters 14 and 15, respectively (0xE and 0xF). ... Shift Out (SO) and Shift In (SI) are ASCII control characters 14 and 15, respectively (0xE and 0xF). ... In telecommunications, a negative-acknowledge character (NAK) is a transmission control character sent by a station as a negative response to the station with which the connection has been set up. ... In telecommunication, the term cancel character has the following meanings: 1. ... In computing, control-Z is a control character in ASCII code, also known as the substitute (SUB) character. ... Substitute character (SUB): A control character that is used in the place of a character that is recognized to be invalid or in error or that cannot be represented on a given device. ... In computing and telecommunication, an escape character is one which has a special meaning in a sequence of characters. ... Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ... Caret notation is a notation for unprintable control characters in ASCII encoding. ... C is a general-purpose, block structured, procedural, imperative computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system. ... Java is a programming language originally developed by Sun Microsystems and released in 1995. ... Wikibooks has a book on the topic of Perl Programming Perl is a dynamic programming language created by Larry Wall and first released in 1987. ... Theres a sucker born every minute is a phrase often credited to P.T. Barnum. ... The user interface is the part of a system exposed to users. ...

Probably the most influential single device on the interpretation of these characters was the Teletype corporation model 33 series, 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 up through the 1980s, lower cost and in some ways less fragile than magnetic tape. In particular, the Teletype 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. 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 faded out. A teleprinter (teletypewriter, teletype or TTY) is a now largely obsolete electro-mechanical typewriter which can be used to communicate typed messages from point to point through a simple electrical communications channel, often just a pair of wires. ... A roll of punched tape Punched tape is an old-fashioned form of data storage, consisting of a long strip of paper in which holes are punched to store data. ...

The use of Control-S (XOFF, an abbreviation for "transmit off") as a handshaking signal warning a sender to stop transmission because of impending overflow, and Control-Q (XON, "transmit on") to resume sending, 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.

Code 127 is officially named "delete" but the Teletype label was "rubout". Since the original standard gave no detailed interpretation for most control codes, interpretations of this code varied. The original Teletype meaning, and the intent of the standard, was to make it an ignored character, the same as NUL (all zeroes). This was specifically useful for paper tape, because punching the all-ones bit pattern on top of an existing mark would obliterate it. Tapes designed to be "hand edited" could even be produced with spaces of extra NULs (blank tape) so that a block of characters could be "rubbed out" and then replacements put into the empty space. A roll of punched tape Punched tape is an old-fashioned form of data storage, consisting of a long strip of paper in which holes are punched to store data. ...

As video terminals began to replace printing ones, the value of the "rubout" character was lost. DEC systems, for example, interpreted "Delete" to mean "remove the character before the cursor," and this interpretation also became common in Unix systems. Most other systems used "Backspace" for that meaning and used "Delete" as it was used on paper tape, to mean "remove the character after the cursor". That latter interpretation is the most common today.

Many more of the control codes have taken on meanings quite different from their original ones. The "escape" character (code 27), for example, was originally intended 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 coopted and has eventually drifted. In modern use, an ESC sent to the terminal usually indicates the start of a command sequence, usually in the form of an ANSI escape code. 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. ANSI escape codes are used to control text formatting and other output options on text terminals that are based on the ANSI X3. ... TECO (pronounced /teekoh/; originally an acronym for [paper] Tape Editor and COrrector, but later Text Editor and COrrector) is a text editor originally developed at the Massachusetts Institute of Technology (MIT) in the 1960s and was modified by just about everybody. With all the dialects included, TECO may have... The correct title of this article is vi. ...

The inherent ambiguity of many control characters, combined with their historical usage, has also created problems when transferring "plain text" files between systems. The clearest example of this is the newline problem on various operating systems. On printing terminals there is no question that you terminate a line of text with both "Carriage Return" and "Linefeed". The first returns the printing carriage to the beginning of the line and the second advances to the next line without moving the carriage. However, requiring two characters to mark the end of a line introduced unnecessary complexity and questions as to how to interpret each character when encountered alone. To simplify matters, plain text files on Unix systems use line feeds alone to separate lines. Similarly, older Macintosh systems, among others, use only carriage returns in plain text files. Various DEC operating systems used both characters to mark the end of a line, perhaps for compatibility with teletypes, and this de facto standard was copied in the CP/M operating system and then in MS-DOS and eventually Microsoft Windows. The DEC operating systems, along with CP/M, tracked file length only in units of disk blocks and used Control-Z (SUB) to mark the end of the actual text in the file (also done for CP/M compatibility in some cases in MS-DOS, though MS-DOS has always recorded exact file-lengths). Control-C (ETX, End of TeXt) might have made more sense, but was already in wide use as a program abort signal. UNIX's use of Control-D (EOT, End of Transmission) appears on its face similar, but is used only from the terminal and never stored in a file. In computing, a newline is a special character or sequence of characters signifying the end of a line of text. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... The DEC logo Digital Equipment Corporation was a pioneering American company in the computer industry. ... Teletype machines in World War II A teleprinter (teletypewriter, teletype or TTY for TeleTYpe/TeleTYpewriter) is a now largely obsolete electro-mechanical typewriter which can be used to communicate typed messages from point to point through a simple electrical communications channel, often just a pair of wires. ... CP/M was an operating system originally created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc. ... Microsofts disk operating system, MS-DOS, was Microsofts implementation of DOS, which was the first popular operating system for the IBM PC, and until recently, was widely used on the PC compatible platform. ... Microsoft Windows is the name of several families of proprietary software operating systems by Microsoft. ...

While the codes mentioned above have retained some semblance of their original meanings, many of the codes originally intended for stream delimiters or for link control on a terminal have lost all meaning except their relation to a letter. Control-A is almost never used to mean "start of header" except on an ANSI magnetic tape. When connecting a terminal to a system, or asking the system to recognize that a logged-out terminal wants to log in, modern systems are much more likely to want a carriage return or an ESCape than Control-E (ENQuire, meaning "is there anybody out there?").

Non-whitespace control characters

RFC 2822 refers to NO-WS-CTL, non-whitespace control characters. These are control characters that do not include carriage return, line feed, and white space characters (see here), i.e.: decimal 1–8, 11–12, 14–31, and 127.

ASCII printable characters

Code 32, the "space" character, denotes the space between words, as produced by the large space-bar of a keyboard. Codes 33 to 126, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. A space is a punctuation convention for providing interword separation in some scripts, including the Latin, Greek, Cyrillic, and Arabic. ...

Seven-bit ASCII provided seven "national" characters and, if the combined hardware and software permit, can use overstrikes to simulate some additional international characters: in such a scenario a backspace can precede a grave accent (which the American and British standards, but only those standards, also call "opening single quotation mark"), a backtick, or a breath mark (inverted vel). The grave accent ( ` ) is a diacritic mark used in written Greek until 1982 (polytonic orthography), French, Catalan, Welsh, Italian, Vietnamese, Scottish Gaelic, Norwegian, Portuguese and other languages. ... The grave accent ( ` ) is a diacritic mark used in written Greek, French, Catalan, Welsh, Italian, Vietnamese, Norwegian, Portuguese and other languages. ... Vel Tamil வேல் is an ancient spear like weapon of Tamils. ...

The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. ... Decimal, or denary, notation is the most common way of writing the base 10 numeral system, which uses various symbols for ten distinct quantities (0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, called digits) together with the decimal point and the sign symbols + (plus) and − (minus... In mathematics and computer science, hexadecimal, base-16, or simply hex, is a numeral system with a radix, or base, of 16, usually written using the symbols 0–9 and A–F, or a–f. ... A space is a punctuation convention for providing interword separation in some scripts, including the Latin, Greek, Cyrillic, and Arabic. ... an exclamation mark An exclamation mark, exclamation point or bang, !, is usually used after an interjection or exclamation to indicate strong feeling. ... For the Wikipedia quotation template, see here. ... Number sign in Arial font Number sign is one name for the symbol #, and is the preferred Unicode name for the codepoint represented by that glyph. ... $ The dollar sign ($) is a symbol primarily used to indicate a unit of currency. ... The percent sign (%) is the symbol used to indicate a percentage (that the preceding number is divided by one hundred). ... The roman ampersand at left is stylized, but the italic one at right reveals its origin in the Latin word An ampersand (&), also commonly called an and sign, is a logogram representing the conjunction and. ... An apostrophe ( ’ ) is a punctuation and sometimes diacritic mark in languages written in the Latin alphabet. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... This article refers to the typographical symbol. ... The plus (+) and minus (−) signs are used universally to represent the operations of addition and subtraction, and have been extended to many other meanings, more or less analogous. ... A comma ( , ) is a punctuation mark. ... A hyphen ( -, or ‐ ) is a punctuation mark. ... This article does not cite any references or sources. ... The slash A slash or stroke, /, is a punctuation mark. ... (Redirected from 0) Zero redirects here. ... Look up one in Wiktionary, the free dictionary. ... “II” redirects here. ... This article discusses the number three. ... This article discusses the number Four. ... Look up five in Wiktionary, the free dictionary. ... Look up six in Wiktionary, the free dictionary. ... Seven Days of Creation - 1765 book, title page 7 (seven) is the natural number following 6 and preceding 8. ... Look up eight in Wiktionary, the free dictionary. ... Look up nine in Wiktionary, the free dictionary. ... The colon (:) is a punctuation mark, visually consisting of two equally sized dots centered on the same vertical line. ... A semicolon (  ;  ) is a punctuation mark. ... For the socioeconomic meaning, see social inequality. ... The equal sign, equals sign, or = is a mathematical symbol used to indicate equality. ... For the socioeconomic meaning, see social inequality. ... The question mark (also known as an interrogation point, query,[1] or eroteme) is a punctuation mark that replaces the full stop at the end of an interrogative sentence. ... The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. ... Decimal, or denary, notation is the most common way of writing the base 10 numeral system, which uses various symbols for ten distinct quantities (0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, called digits) together with the decimal point and the sign symbols + (plus) and − (minus... In mathematics and computer science, hexadecimal, base-16, or simply hex, is a numeral system with a radix, or base, of 16, usually written using the symbols 0–9 and A–F, or a–f. ... Look up @ in Wiktionary, the free dictionary A commercial at, @, also called an at symbol, an at sign, or just at, is a symbolic abbreviation for the word at. ... This article needs additional references or sources for verification. ... Look up B, b in Wiktionary, the free dictionary. ... Look up C, c in Wiktionary, the free dictionary. ... Look up D, d in Wiktionary, the free dictionary. ... Look up E, e in Wiktionary, the free dictionary. ... Look up F, f in Wiktionary, the free dictionary. ... The letter G is the seventh letter in the Latin alphabet. ... Look up H, h in Wiktionary, the free dictionary. ... Look up I, i in Wiktionary, the free dictionary. ... J# redirects here for technical reasons; see J Sharp. ... Look up K, k in Wiktionary, the free dictionary. ... Look up L, l in Wiktionary, the free dictionary. ... Look up M, m in Wiktionary, the free dictionary. ... Look up N, n in Wiktionary, the free dictionary. ... Look up O, o in Wiktionary, the free dictionary. ... Look up P, p in Wiktionary, the free dictionary. ... Look up Q, q in Wiktionary, the free dictionary. ... Look up R, r in Wiktionary, the free dictionary. ... Look up S, s in Wiktionary, the free dictionary. ... Its name in English is tee . ... Look up U, u in Wiktionary, the free dictionary. ... Look up V, v in Wiktionary, the free dictionary. ... Look up W, w in Wiktionary, the free dictionary. ... Look up X, x in Wiktionary, the free dictionary. ... This article does not cite any references or sources. ... Look up Z, z in Wiktionary, the free dictionary. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... First introduced in 1960 by Bob Bemer, the backslash, , is a typographical mark (glyph) used chiefly in computing. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... A caret in the Arial font Caret is the name for the symbol ^ in ASCII and some other character sets. ... The underscore _ is the character with ASCII value 95. ... The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. ... Decimal, or denary, notation is the most common way of writing the base 10 numeral system, which uses various symbols for ten distinct quantities (0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, called digits) together with the decimal point and the sign symbols + (plus) and − (minus... In mathematics and computer science, hexadecimal, base-16, or simply hex, is a numeral system with a radix, or base, of 16, usually written using the symbols 0–9 and A–F, or a–f. ... The grave accent ( ` ) is a diacritic mark used in written Greek until 1982 (polytonic orthography), French, Catalan, Welsh, Italian, Vietnamese, Scottish Gaelic, Norwegian, Portuguese and other languages. ... This article needs additional references or sources for verification. ... Look up B, b in Wiktionary, the free dictionary. ... Look up C, c in Wiktionary, the free dictionary. ... Look up D, d in Wiktionary, the free dictionary. ... Look up E, e in Wiktionary, the free dictionary. ... Look up F, f in Wiktionary, the free dictionary. ... The letter G is the seventh letter in the Latin alphabet. ... Look up H, h in Wiktionary, the free dictionary. ... Look up I, i in Wiktionary, the free dictionary. ... J# redirects here for technical reasons; see J Sharp. ... Look up K, k in Wiktionary, the free dictionary. ... Look up L, l in Wiktionary, the free dictionary. ... Look up M, m in Wiktionary, the free dictionary. ... Look up N, n in Wiktionary, the free dictionary. ... Look up O, o in Wiktionary, the free dictionary. ... Look up P, p in Wiktionary, the free dictionary. ... Look up Q, q in Wiktionary, the free dictionary. ... Look up R, r in Wiktionary, the free dictionary. ... Look up S, s in Wiktionary, the free dictionary. ... Its name in English is tee . ... Look up U, u in Wiktionary, the free dictionary. ... Look up V, v in Wiktionary, the free dictionary. ... Look up W, w in Wiktionary, the free dictionary. ... Look up X, x in Wiktionary, the free dictionary. ... This article does not cite any references or sources. ... Look up Z, z in Wiktionary, the free dictionary. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... Vertical bar, verti-bar, vertical line, divider line, or pipe is the name of the character (|). Broken bar (¦) is a separate character. ... For technical reasons, :) and some similar combinations starting with : redirect here. ... A tilde. ...

Structural features

• The digits 0–9 are represented with their values in binary prefixed with 0011 (this means that converting BCD to ASCII is simply a matter of taking each BCD nibble separately and prefixing 0011 to it).
• Lowercase and uppercase letters only differ in bit pattern by a single bit, simplifying case conversion to a range test (to avoid converting characters that are not letters) and a single bitwise operation. Fast case conversion is important because it is often used in case-ignoring search algorithms.
• In contrast with EBCDIC, the lowercase and uppercase letters each occupy 26 consecutive positions.

In computing and electronic systems, Binary-coded decimal (BCD) is an encoding for decimal numbers in which each digit is represented by its own binary sequence. ... In computer programming, a bitwise operation operates on one or two bit patterns or binary numerals at the level of their individual bits. ... EBCDIC (Extended Binary Coded Decimal Interchange Code) is an 8-bit character encoding (code page) used on IBM mainframe operating systems, like z/OS, OS/390, VM and VSE, as well as IBM minicomputer operating systems like OS/400 and i5/OS. It is also employed on various non-IBM...

Aliases

RFC 1345 (published in June 1992) and the IANA registry of character sets (ongoing), both recognize the following case-insensitive aliases for ASCII as suitable for use on the Internet:

• ANSI_X3.4-1968 (canonical name)
• ANSI_X3.4-1986
• ASCII (with ASCII-7 and ASCII-8 variants)
• US-ASCII (preferred MIME name)
• us
• ISO646-US
• ISO_646.irv:1991
• iso-ir-6
• IBM367
• cp367
• csASCII

Of these, only the aliases "US-ASCII" and "ASCII" have achieved widespread use. One often finds them in the optional "charset" parameter in the Content-Type header of some MIME messages, in the equivalent "meta" element of some HTML documents, and in the encoding declaration part of the prolog of some XML documents. Multipurpose Internet Mail Extensions (MIME) is an Internet Standard that extends the format of e-mail to support: text in character sets other than US-ASCII; non-text attachments; multi-part message bodies; and header information in non-ASCII character sets. ... HTML, short for Hypertext Markup Language, is the predominant markup language for the creation of web pages. ... The Extensible Markup Language (XML) is a general-purpose markup language. ...

Variants

As computer technology spread throughout the world, different standards bodies and corporations developed many variations of ASCII in order 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 mis-apply that term to cover all variants, including those that do not preserve ASCII's character-map in the 7-bit range. The term extended ASCII (or high ASCII) describes eight-bit or larger character encodings that include the standard seven-bit ASCII characters as well as others. ...

The PETSCII Code used by Commodore International for their 8-bit systems is probably unique among post-1970 codes in being based on ASCII-1963 instead of the far more common ASCII-1967. PETSCII (PET Standard Code of Information Interchange), also known as CBM ASCII, is the variation of the ASCII character set used in Commodore (CBM)s 8-bit home computers, starting with the PET from 1977 and including the VIC-20, C64, Plus/4, C16 and C128. ... Commodore, the commonly used name for Commodore International, was an American electronics company based in West Chester, Pennsylvania which was a vital player in the home/personal computer field in the 1980s. ...

Incompatibility vs interoperability

ISO 646 (1972), the first attempt to remedy the pro-English-language bias, created compatibility problems, since it remained a 7-bit character-set. It made no additional codes available, so it reassigned some in language-specific variants. It thus became impossible to know what character a code represented without knowing which variant to work with, and text-processing systems could generally cope with only one variant anyway. ISO 646 is an ISO standard that specifies a 7 bit character code from which several national standards are derived, the best known of which is ASCII. Since the portion of ISO 646 shared by all countries specified only the letters used in the English alphabet, other countries using the...

Eventually, improved technology brought out-of-band means to represent the information formerly encoded in the eighth bit of each byte, freeing this bit to add another 128 additional character-codes for new assignments.

For example, IBM developed 8-bit code pages, such as 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. International Business Machines Corporation (known as IBM or Big Blue; NYSE: IBM) is a multinational computer technology and consulting corporation headquartered in Armonk, New York, USA. The company is one of the few information technology companies with a continuous history dating back to the 19th century. ... Code page is the traditional IBM term used for a specific character encoding table: a mapping in which a sequence of bits, usually a single octet representing integer values 0 through 255, is associated with a specific character. ... IBM PC or MS-DOS code page 437, often abbreviated CP437 and also known as DOS-US or OEM-US, is the original character set of the IBM PC, circa 1981. ... The smiley has gone through many incarnations over the years, but it consistently retains the same features. ... Instructions on how to use the directory command. ... IBM PC (IBM 5150) with keyboard and green screen monochrome monitor (IBM 5151), running MS-DOS 5. ... The DEC logo Digital Equipment Corporation was a pioneering American company in the computer industry. ... The Multinational Character Set is a character encoding created by Digital Equipment Corporation for use in the popular VT220 terminal. ... The VT220 was a terminal produced by Digital Equipment Corporation from 1983 to 1987. ... A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system. ...

Eight-bit standards such as ISO/IEC 8859 (derived from the DEC-MCS) and Mac OS Roman developed as true extensions of ASCII, leaving the original character-mapping intact and just adding additional values above the 7-bit range. ISO 8859, more formally ISO/IEC 8859, is a joint ISO and IEC standard for 8-bit character encodings for use by computers. ... Mac OS Roman is a character encoding primarily used by Mac OS to represent text. ...

This enabled the representation of a broader range of languages, but these standards continued to suffer from incompatibilities and limitations. Still, ISO-8859-1, its variant Windows-1252 (often mislabeled as ISO-8859-1 even by Microsoft software) and original 7-bit ASCII remain the most common character encodings in use today. ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding defined by ISO. It encodes what it refers to as Latin alphabet no. ... ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding defined by ISO. It encodes what it refers to as Latin alphabet no. ...

Unicode fix

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 basically uses 7-bit codes, Unicode and the UCS use relatively abstract "code points": non-negative integer numbers that map, using different encoding forms and schemes, to sequences of one or more 8-bit bytes. To permit backward compatibility, Unicode and the UCS assign the first 128 code points to the same characters as ASCII, and the first 256 code points to the same characters as ISO 8859-1 (Latin 1). One can therefore think of ASCII as a 7-bit encoding scheme for a very small subset of Unicode and of the UCS. Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ... The international standard ISO/IEC 10646 defines the Universal Character Set (UCS) as a character encoding. ... ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding of the Latin alphabet. ...

The popular UTF-8 (and UTF-7) encoding-form prescribes the use of one to four 8-bit code values for each code point character, and equates exactly to ASCII for the code values below 128. Other encoding forms such as UTF-16 resemble ASCII in how they represent the first 128 characters of Unicode, but tend to use 16 or 32 bits per character, so they require conversion for compatibility. UTF-8 (8-bit Unicode Transformation Format) is a variable-length character encoding for Unicode created by Ken Thompson and Rob Pike. ... UTF-7 (7-bit Unicode Transformation Format) is a variable-length character encoding that was proposed for representing Unicode-encoded text using a stream of ASCII characters, for example for use in Internet e-mail messages. ... In computing, UTF-16 is a 16-bit Unicode Transformation Format, a character encoding form that provides a way to represent a series of abstract characters from Unicode and ISO/IEC 10646 as a series of 16-bit words suitable for storage or transmission via data networks. ...

Order

Collation of data is sometimes done in ASCII-code order rather than "standard" alphabetical order. The main deviations are: Alphabetical redirects here. ...

• capitals come before lowercase letters, i.e. "Z" before "a"
• characters such as "é" come after "z"

The blend word ASCIIbetical is sometimes used for this order.^[5] It has been suggested that this article or section be merged into Portmanteau. ...

A refined version of this order converts uppercase letters to lowercase before comparing ASCII values.

Trivia

• The abbreviation ASCIIZ or ASCIZ refers to a null-terminated ASCII string (also known as a C string).
• Asteroid 3568 ASCII is named after the character encoding.

In computer programming and formal language theory, (and other branches of mathematics), a string is an ordered sequence of symbols. ... The null character (also null terminator) is a character with the value zero, present in the ASCII and Unicode character sets, and available in nearly all mainstream programming languages. ... In various branches of mathematics and computer science, strings are sequences of various simple objects (symbols, tokens, characters, etc. ... In computing, C strings are character sequences stored as one-dimensional character arrays and terminated with a null character (0). The name refers to the ubiquitous C programming language using this string representation, and is used elsewhere to distinguish this often-used representation from others. ... 3568 ASCII is a small main belt asteroid. ...

See also

• ANSI
• ASCII art
• ASCII games
• Control character
• Text file
• Bob Bemer
• EBCDIC
• Unicode
• Latin characters in Unicode
• ASCII ribbon
• Binary

The American National Standards Institute or ANSI (pronounced an-see) is a nonprofit organization that oversees the development of standards for products, services, processes and systems in the United States. ... ASCII art, an artistic medium relying primarily on computers for presentation, consists of pictures pieced together from characters (preferably from the 95 printable characters defined by ASCII). ... An ASCII game is a game using characters on the screen instead of more complicated graphics using pixels. ... In computing, a control character or non-printing character, is a code point (a number) in a character set that does not in itself represent a written symbol. ... It has been suggested that this article or section be merged with Plain text. ... Robert William Bemer (February 8, 1920 – June 22, 2004) was a computer scientist best known for his work at IBM during the late 1950s and early 1960s. ... EBCDIC (Extended Binary Coded Decimal Interchange Code) is an 8-bit character encoding (code page) used on IBM mainframe operating systems, like z/OS, OS/390, VM and VSE, as well as IBM minicomputer operating systems like OS/400 and i5/OS. It is also employed on various non-IBM... Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ... Unicode as of version 5. ... The ASCII ribbon campaign is an internet phenomenon started in 1998 advocating that the Simple Mail Transfer Protocol used for Internet e-mail not include binary information encoded within. ... The binary numeral system, or base-2 number system, is a numeral system that represents numeric values using two symbols, usually 0 and 1. ...

ASCII extensions

(where all ASCII printable characters are identical to ASCII)

• Extended ASCII
• UTF-8
• ISO 8859
• ISCII
• VISCII
• Windows code pages
• Mac Roman

The term extended ASCII (or high ASCII) describes eight-bit or larger character encodings that include the standard seven-bit ASCII characters as well as others. ... UTF-8 (8-bit Unicode Transformation Format) is a variable-length character encoding for Unicode created by Ken Thompson and Rob Pike. ... ISO 8859, more formally ISO/IEC 8859, is a joint ISO and IEC standard for 8-bit character encodings for use by computers. ... ISCII (Indian Script Code for Information Interchange) is a coding scheme for representing various Indic scripts as well as a Latin-based script with diacritic marks used to depict Romanised Indic languages. ... VISCII stands for Vietnamese Standard Code for Information Interchange. ... Microsoft uses two main groups of code pages in Windows. ... The Mac OS Roman character set Mac-Roman encoding is a one byte character encoding system, traditionally used by Mac OS. In Mac OS X, it has been replaced with Unicode. ...

ASCII variants

(where some ASCII printable characters have been replaced)

• ISO 646
• ATASCII - Atari Standard Code for Information Interchange
• PETSCII - PET Standard Code of Information Interchange, also known as CBM ASCII
• ZX Spectrum character set
• YUSCII - Yugoslav Standard Code for Information Interchange
• Galaksija character set - character set of Galaksija kit computer

ISO 646 is an ISO standard that specifies a 7 bit character code from which several national standards are derived, the best known of which is ASCII. Since the portion of ISO 646 shared by all countries specified only the letters used in the English alphabet, other countries using the... The ATASCII character set, from ATARI Standard Code for Information Interchange, alternatively ATARI ASCII, is the variation on ASCII used in the Atari 8-bit family of home computers. ... This article is about a corporate game company. ... PETSCII (PET Standard Code of Information Interchange), also known as CBM ASCII, is the variation of the ASCII character set used in Commodore (CBM)s 8-bit home computers, starting with the PET from 1977 and including the VIC-20, C64, Plus/4, C16 and C128. ... The PET (Personal Electronic Transactor) was a home-/personal computer produced by Commodore starting in the late 1970s. ... Commodore, the commonly used name for Commodore International, was an American electronics company based in West Chester, Pennsylvania which was a vital player in the home/personal computer field in the 1980s. ... The ZX Spectrum character set is the variant of ASCII used in the British Sinclair Spectrum computers. ... YUSCII was an informal name for JUS I.B1. ... This article or section does not cite any references or sources. ... Galaksija on the cover of Računari u vašoj kući The Galaksija (Galaxy) was originally a kit-built computer designed by Voja Antonić. It was featured in the special edition Računari u vašoj kući (Computers in your home) of a popular science magazine of the... Galaksija on the cover of Računari u vašoj kući The Galaksija (Galaxy) was originally a kit-built computer designed by Voja Antonić. It was featured in the special edition Računari u vašoj kući (Computers in your home) of a popular science magazine of the...

Further reading

• Tom Jennings. World Power Systems:Texts:Annotated history of character codes. Retrieved on 2006-11-06.

For the Manfred Mann album, see 2006 (album). ... November 6 is the 310th day of the year (311th in leap years) in the Gregorian calendar. ...

References

1. ^ Brandel, Mary. 1963: The Debut of ASCII: History of the origin of the ASCII standard.
2. ^ International Organization for Standardization (December 1, 1975). "The set of control characters for ISO 646". Internet Assigned Numbers Authority Registry. Alternate U.S. version: [1]. Accessed August 7, 2005.
3. ^ Internet Assigned Numbers Authority (January 28, 2005). "Character Sets". Accessed August 7, 2005.
4. ^ (January 1, 1995) A Tex Primer for Scientists (in English). CRC Press. ISBN 0-8493-7159-7. 
5. ^ ASCIIbetical.

December 1 is the 335th (in leap years the 336th) day of the year in the Gregorian calendar. ... Year 1975 (MCMLXXV) was a common year starting on Wednesday (link will display full calendar) of the Gregorian calendar. ... August 7 is the 219th day of the year (220th in leap years) in the Gregorian calendar. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... January 28 is the 28th day of the year in the Gregorian calendar. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... August 7 is the 219th day of the year (220th in leap years) in the Gregorian calendar. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. ... Year 1995 (MCMXCV) was a common year starting on Sunday (link will display full 1995 Gregorian calendar). ...

External links

• ASCII-Table and ASCII-Charconverter
• The ASCII subset of Unicode
• A history of ASCII, its roots and predecessors by Tom Jennings, October 29, 2004 (accessed December 17, 2005)
• A pronunciation guide for ASCII characters
• ASCII Chart, how to send documents "in ASCII", etc
• Online Encoder/Decoder for ASCII, HEX, Binary, Base64, etc with MD2, MD4, MD5, SHA1+2, CRC, and other hashing algorithms
• Interactive AJAX-style ASCII (and Unicode) Decoder Table
• Printable ASCII Table
• Another Printable ASCII Table
• ASCII to 8-bit binary converter and source code
• ASCII to ASCII CODE converter and source code
• Convert PDF, PostScript, WMF and EMF to ASCII
• ANSI INCITS 4-1986 (R2002) Information Systems - Coded Character Sets - 7-Bit American National Standard Code for Information Interchange (7-Bit ASCII)

Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ... Tom Jennings (born 1955 as Thomas Daniel Jennings in Boston, Massachusetts) is the creator of FidoNet, the first message and file networking system for BBSes. ... October 29 is the 302nd day of the year (303rd in leap years) in the Gregorian calendar. ... shelby was here 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... December 17 is the 351st day of the year (352nd in leap years) in the Gregorian calendar. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ...