APC, or Alternative PHP Cache, is a PHP module that caches the output code of database-driven script software apps. Dynamic PHP websites hold their content within a database which is accessed whenever a visitor loads a page. The content which has to be viewed is retrieved and the code is parsed and compiled prior to it being delivered to the website visitor. All of these actions need some processing time and require reading and writing on the server for every single page that is loaded. While this can't be avoided for websites with constantly changing content material, there are a lot of sites that offer the very same content on many of their webpages constantly - blogs, informational portals, hotel and restaurant Internet sites, and many others. APC is quite useful for such websites as it caches the already compiled code and displays it any time visitors browse the cached webpages, so the code doesn't have to be parsed and compiled again. Not only will this lower the server load, but it will also boost the speed of any Internet site several times.