GeSHi or Generic Syntax Highlighter is a free software library that allows syntax highlighting of source code for several markup and programming languages. The program is written in PHP and is bundled or available as an add-on in popular web-based applications, such as Dokuwiki, Drupal, Mambo, MediaWiki (see extension), phpBB and WikkaWiki. Wikipedia used GeSHi as its primary syntax highlighter until 2015.
Among its notable features:
- Fully CSS-driven output
- Supports about 220 markup and programming languages
- Extensibility via custom language files
- XHTML 1.1 and CSS Level 2 compliance
- Auto-caps/noncaps of keywords
- Line numbering
- Word wrapping
- Automatic generation of links to programming language documentation
GeSHi was originally designed as a module to introduce syntax highlighting in the phpBB board system. Later, it was made to work without a phpBB as a stand-alone library.
After a long time of inactivity the project was handed over to Benny Baumann on March 15, 2008.
Software which utilises GeSHi to colour files
Free GeSHi WebService