character encoding

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Related to Character encodings: character set, Text encoding

character encoding

(character)
(Or "character encoding scheme") A mapping of binary values to code positions and back; generally a 1:1 (bijective) mapping.

In the case of ASCII, this is generally a f(x)=x mapping: code point 65 maps to the byte value 65, and vice versa. This is possible because ASCII uses only code positions representable as single bytes, i.e., values between 0 and 255, at most. (US-ASCII only uses values 0 to 127, in fact.)

Unicode and many CJK coded character sets use many more than 255 positions, requiring more complex mappings: sometimes the characters are mapped onto pairs of bytes (see DBCS). In many cases, this breaks programs that assume a one-to-one mapping of bytes to characters, and so, for example, treat any occurrance of the byte value 13 as a carriage return. To avoid this problem, character encodings such as UTF-8 were devised.
References in periodicals archive ?
Babel: Multilingual bookmark page -- page in various character encodings
Before Unicode, 8-bit character encoding with its built-in limit of 256 characters could have the same character code number represent a different character in different alphabets.
It should be noted also that UTF-8 should always be specified as the character encoding system with text containing two or more non-Latin scripts.
Counting characters, measuring string length in the presence of variable-length character encodings and combining characters
In addition, the Kinecta Interact AdaptiveContent transformation capabilities can now handle content encoded in the most popular single- and double-byte character encodings, including Unicode.
Previous versions of Windows operating systems and character encodings do not support the Euro, the currency symbol for the combined European Community.