Markup language

A markup language is a system for annotating a document in a way that is syntactically distinguishable from the text.

Description

The idea and terminology evolved from the "marking up" of paper manuscripts, i.e., the revision instructions by editors, traditionally written with a blue pencil on authors' manuscripts.

Tags

In digital media this "blue pencil instruction text" was replaced by tags.

Tags are metadata: they describe the content and format of the text.

Examples

Examples include typesetting instructions such as those found in troff, TeX and LaTeX, or structural markers such as XML tags. Markup instructs the software that displays the text to carry out appropriate actions, but is omitted from the version of the text that users see.

Some markup languages, such as HTML, have pre-defined presentation semantics -- meaning that their specification prescribes how to present the structured data.

Others, such as XML, do not have pre-defined semantics, but instead require you to provide your own semantics, by inventing names and other properties for your XML tags.

See also

• Formal language
• HTML
• HTML5
• Human-readable medium
• Metadata
• Syntax (logic)
• Syntax (programming languages)
• Tag (markup language)
• XHTML
• XML

External Links

• Markup language @ Wikipedia