APC, which is an acronym for Alternative PHP Cache, is a framework used for caching the compiled source code of a given script app, which could speed up a database-driven website several times. Any time a PHP webpage is opened, the script pulls the content which has to be shown from a database, parses and compiles the program code, and the result is displayed to the website visitor. While this is necessary for sites with regularly changing content, it is a total waste of processing time and resources for an Internet site that doesn't change, like an informational portal that displays the exact same content on a regular basis. As soon as the webpages for such a website are compiled, APC caches them and delivers them whenever a visitor opens them. As this saves the time to request content from the database and to parse and compile the code, the website will load much faster. APC is very effective particularly for scripts with large source code.