ASCII
Acronym for the American Standard
Code for Information Interchange. Pronounced ask-ee, ASCII is a code for
representing English characters as numbers, with each letter assigned a number
from 0 to 127. For example, the ASCII code for uppercase M is 77. Most
computers use ASCII codes to represent text, which makes it possible to
transfer data from one computer to another.
Text files stored in ASCII format
are sometimes called ASCII files. Text editors and word processors are usually
capable of storing data in ASCII format, although ASCII format is not always
the default storage format. Most data files, particularly if they contain
numeric data, are not stored in ASCII format. Executable programs are never
stored in ASCII format.
The standard ASCII character set
uses just 7 bits for each character. A larger character set, known as extended
ASCII or high ASCII, uses 8 bits, which gives it 128 additional characters.The
extra characters are used to represent non-English characters, graphics
symbols, and mathematical symbols. Several companies and organizations have
proposed extensions for these 128 characters. The ANSI standards organization
has defined a standard character set for the codes 128 through 255 (see under
ANSI character set) but not all computers conform to it.
Another set of codes that is used
on large IBM computers is EBCDIC.