afterBURNER*Cache is a tool to speed up web applications written in PHP. It works by caching inside the web server compiled PHP code (the first time it's executed) so that the next time the same script is called it is simply restored, already compiled, from the cache with big savings in terms of execution time. Caching and saving scripts at compile time can be a big performance win, especially if your PHP script is complex and makes heavy use of libraries.