Unicode Explained

Language Metadata

Metadata is data about data. For example, the string “elf” is text data, and we can

associate with it the metadata that the text is in English. This does not change the

identity of characters in the data, but it may affect the interpretation and processing of

the data. If accompanied with metadata that says that the string “elf” is in German, the

correct interpretation would be that it is a numeral that means “11” (the word is a

cognate of English “eleven”).

Normally metadata is invisible, when represented using a digital data format that has

provisions for metadata. In plain text, you cannot make a distinction between data and

metadata. You can write “This document is in English” if you like, but structurally that

would be just part of the text. In markup languages and in data formats used by word

processors, metadata can be stored and processed separately.

It is difficult to specify what constitutes a language, but in this context, “language”

means definitely “human language” as opposite to computer languages such program-

ming, command, and data description languages. Text in a computer language may be

characterized as belonging to some human language, to some extent. For example, for

the purposes of speech synthesis, comments and variable names in computer source

programs need to be interpreted as belonging to some human language.

Need for Language Information

In data processing, ...