Memcached is a distributed memory caching platform, which is used to supercharge the loading speed of database-driven websites by caching the calls and the replies between the website visitor and the server. To put it in simple terms, anytime a particular page on such a site is opened, the script connects to its database to get the info that should be shown to the visitor. In case the latter clicks a hyperlink to go to some other page, the entire procedure is executed again and this results in plenty of database calls and excessive server load, even more so if the site has lots of simultaneous visitors. Memcached "memorizes" this information exchange, so in case any of these pages is visited again, the script no longer needs to pull any info from the database, since everything is provided by the Memcached platform. In this way, the overall load speed of your website will increase and you will get more pleased visitors and they will be able to browse your website much faster. Besides, the Memcached platform updates its cache if any info in the database is changed, so the users will never see old content.