Memcached is a memory caching platform, which is used to supercharge the speed of database-driven Internet sites by caching the calls and the responses between the website visitor and the server. To put it in simple terms, every time a given page on such a site is requested, the script queries its database to request the info that should be displayed to the visitor. In case the latter clicks on a link to go to some other web page, the entire operation is carried out again and this results in lots of database calls and excessive load on the server, particularly if the site has lots of simultaneous visitors. Memcached "memorizes" this information exchange, so if any of these web pages is opened again, the script no longer has to cull any info from the database, since everything is delivered by the Memcached platform. In this way, the overall loading speed of your website will "soar" and you will have more gratified visitors and they’ll be able to navigate through your site much faster. Plus, Memcached updates its cache when any content in the database is modified, so the visitors will never end up seeing out-of-date data.