Alternative PHP Cache, or APC, is a module for Apache servers which is employed to cache the output code of script applications. It is very effective for scripts with large source code and will accelerate such a site up to 3 times. PHP sites are dynamic and each time a visitor opens a web page, the script hooks up to a database to retrieve some content, and then the code is parsed and compiled prior to it being shown to the site visitor. If the output code doesn't change however, that is the case with Internet sites which show identical content all of the time, these actions result in excessive reading and writing. What APC does is that it caches the already compiled program code and delivers it whenever visitors browse a site, so the database doesn't need to be accessed and the program code does not need to be parsed and compiled again and again, which in turn decreases the Internet site loading time. The module can be quite efficient for informational sites, blogs, portfolios, and many others.