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Multilingual Computing

SIL contributions

These are some SIL contributions to research and development in the area of multilingual computing:

Other resources

About multilingual computing in general:

Resources for software developers:

On developing a truly multilingual World Wide Web:

Character encoding and rendering

Fundamental to the problem of multilingual computing is the problem of character encoding and rendering. Below is a glossary of key terms that arise in this area; basic definitions are supplemented with pointers to further information resources.


American Standard Code for Information Interchange. A standard character set that maps character codes 0 through 127 onto control functions, punctuation marks, digits, upper case letters, lower case letters, and other symbols.

ASCII file

A data file that contains only character codes in the range 0 to 127 and in which all the codes are to be interpreted by their significance in the ASCII standard.

base character

A character to which an overstriking diacritic is added.


The minimal unit of encoding for text files. A character typically corresponds to a single graphic sign of a writing system, like a letter of the alphabet or a punctuation mark.

character code

A numerical code in a data file which represents a particular character in text. For instance, in the ASCII standard, 65 represents upper-case A.

character set

The full set of character codes used for encoding a particular language or writing system (also known as, coded character set).

Some sources that discuss concepts and terminology:

These sources describe the contents of particular character sets:

collating sequence

The sorting order for all the characters in a character set.

composite character

A single character which is a composite of two or more other characters. For instance, à is a composite of a (the base character) and ` (a diacritic).


A small mark (such as an accent mark) added above, below, before, or after a base character to modify its pronunciation or significance.


The manner in which information is represented in computer data files. Character encoding refers specifically to the codes used to represent characters. (See also text encoding.)


A collection of bitmaps or outlines which supply the graphic rendering of every character in a character set.

font system

A subcomponent of an operating system which gives all programs and data files access to multiple fonts for rendering characters.

For instance,


The process of converting a stream of encoded characters (that is, character codes) to their correct graphic appearance on a terminal or printer.

The seminal work on encoding versus rendering is:

special character

A character that is not available in one of the character sets already supported on a computer system.


A character set which attempts to include every character from all the major writing systems of the world. It uses two bytes (16 bits) to encode each character. In its current version (2.0), the Unicode standard contains 38,885 distinct coded characters from 25 scripts (including the International Phonetic Alphabet).



A subcomponent of the Macintosh operating system (version 7.1 and later) which gives programs access to script interface systems for multiple non-Roman writing systems.

Some relevant publications: