Alternative PHP Cache, or APC, is a module for Apache web servers that is used to cache the output code of script apps. It is very efficient for scripts with large source code and can speed up such a website as much as three times. PHP websites are dynamic and every time a website visitor opens some web page, the script connects to a database to retrieve some content, then the code is parsed and compiled before it's displayed to the website visitor. In case the output code doesn't change however, that is the case with sites which show identical content at all times, these actions result in needless reading and writing. What APC does is that it caches the previously compiled code and delivers it each time visitors browse an Internet site, so the database doesn't have to be accessed and the program code does not have to be parsed and compiled continuously, which in turn reduces the website loading time. The module can be really helpful for informational websites, blogs, portfolios, etc.