GeSHi - Generic Syntax Highlighter

GeSHi started can create a generic syntax highlighter for the phpBB forum system, but has been generalized to this project. GeSHi aims to be a simple but powerful highlighting class. It has support for a wide range of popular languages, easy to add a new language for highlighting, and highly customisable output formats. GeSHi supports PHP5 and Windows, and has even been used to highlight code on ASP pages. Numerous blogs, wikis and forums use GeSHi, including Dokuwiki, Mambo, phpBB and WikkaWiki.