[Pronounced ‘Askee’; The abbreviation of, and the common term for, the American Standard Code for Information Interchange
]. Also ASCII code
. A set of computer codes devised in 1968 and standardized in 1982 as a means of storing and transmitting (American) English texts. The standard code covers 32 non-displayed control characters (such as ‘start of text’ and ‘carriage return’) and 96 displayed alphanumeric and other characters, every letter or other symbol having a number from 0 to 128: for example, 33 for!
, 36 for $
, 65 for A
, 66 for B
, 97 for a
, and 98 for b
. An ASCII keyboard
contains all and only such symbols and enables them to be directly coded; ASCII files
are text files set in ASCII
only. The prime purpose of the code is compatibility among electronic networks, texts being composed in, or converted to, ASCII in order to be transmitted and received successfully. The system, at first used only in North America
, has been rapidly adopted worldwide; however, because the standard code is inadequate for complex texts and for languages with writing conventions different from English, an Extended ASCII
has been developed, containing letters with diacritical marks, some vulgar fractions, monetary symbols such as for the pound and yen, and a range of graphic symbols (255 in all). See CHARACTER SET
ASCII or American Standard Code for Information Interchange, a set of codes used to represent letters, numbers, a few symbols, and control characters. Originally designed for teletype operations, it has found wide application in computers. A seven-digit (or seven-bit) binary number (see binary system) can represent one of 128 distinct codes. Thus, in decimal equivalents, the series
"72, 69, 76, 76, 79"
represents the letters
"h, e, l, l, o"
in ASCII. With the introduction of its personal computer in 1981, the International Business Machines Company (IBM) increased the number of available characters to 256 by using an eight-bit byte. This IBM-extended ASCII set has become a de facto standard. However, the inability of US-ASCII to correctly represent many other languages became an obvious and intolerable misfeature as computer use outside the United States and United Kingdom increased. As a consequence, national extensions to US-ASCII were developed that were incompatible with one another. This in turn led to the standardization of 16-bit (or
) and 32-byte character sets, such as Unicode, that could accommodate large numbers of linguistic and other symbols.
ASCII (or Ascii) Acronym for American standard code for information interchange.
A standard character encoding scheme introduced in 1963 and used widely on many machines. It is a 7-bit code with no parity recommendation, providing 128 different bit patterns. The character set
is shown in the table, together with the control characters (see also ISO-7
International 8-bit codes that are extensions of ASCII have been published by ISO in the series of ISO 8859. In addition to several Latin alphabets
covering English and various other European languages, there are also Cyrillic, Arabic, Greek, and Hebrew code tables.
See also character set
/ ˈaskē/ Comput.
American Standard Code for Information Interchange, a set of digital codes representing letters, numerals, and other symbols, widely used as a standard format in the transfer of text between computers.
Computing American Standard Code for Information Interchange