An Acronym for American Standard Code for Information Interchange.

The ANSI X3.4 standard specifying a character set with 95 characters with codes ranging from 32 to 126 (0x20-0x7E). The codes from 0 to 31 have come to be known as control characters and are not specified by ASCII. Neither is any code beyond 126, since ASCII was designed strictly as a 7-bit encoding. It was published in 1968 and is by far the most successful and popular encoding ever conceived.

Almost all 8-bit encodings (such as ISO 646 and the wildly popular ISO 8859 tables) contain ASCII as their lower half. The only exception with any wide acceptance at all is EBCDIC.

See ascii(7).