- For alternate meanings, see character.
In computer terminology, a character is a unit of information
that roughly corresponds to a grapheme, or written symbol, of a
natural language, such as a letter, numeral, or punctuation mark.
The concept also includes control characters, which do not correspond
to natural language symbols but to other bits of information used to process
texts of the language, such as instructions to printers
or other devices that display such texts.
It is important in some contexts to make the distinction that a character
is a unit of information, and does not imply any particular physical
appearance.
For example, the Hebrew letter "Aleph" is often used by mathematicians to
denote certain kinds of infinity, but also of course in ordinary Hebrew text.
In Unicode, for example, these two uses are different characters and are
signified by two different codes, though they may look identical.
Conversely, the Chinese ideogram for "water" may have a slightly different
appearance in Japanese texts than it does in Chinese texts, and local typefaces
may reflect this.
But they nonetheless represent the same information, are considered the same
character, and share the same Unicode value.
The term glyph is used to describe a particular physical appearance
of a symbol.
Computers and communication equipment represent characters using a
character encoding that matches each character with an integer that can be
stored and manipulated.
The most common such encoding is ASCII, though the more versatile
Unicode is quickly becoming popular.
See also