APC, which means Alternative PHP Cache, is a framework used for caching the compiled source code of a script app, which could boost a database-driven website several times. When a PHP page is accessed, the script pulls the site content that needs to be loaded from a database, parses and compiles the program code, then the result is shown to the site visitor. While this is necessary for websites with constantly changing content, it is a total waste of processing time and resources for an Internet site that does not change, for example an informational portal that displays the exact same content on a regular basis. As soon as the web pages for such a site are compiled, APC caches them and delivers them each time a visitor accesses them. As this saves the time to get content from the database and to parse and compile the program code, your website will load considerably quicker. APC is very effective especially for scripts with massive source code.