Memcached is a memory caching system, which is used to enhance the speed of database-powered websites by caching the queries and the responses between the user and the server. Simply put, anytime a specific web page on such a site is visited, the script calls its database to fetch the information that should be displayed to the website visitor. In case the latter clicks on a link to open a different page, the whole process is executed again and this leads to numerous database calls and higher server load, especially if the website has a lot of simultaneous visitors. Memcached "memorizes" this information exchange, so in case any of these web pages is accessed again, the script no longer has to call any information from the database, as everything is provided by the caching platform. Thus, the overall load speed of your website will increase and you’ll have more satisfied visitors and they will be able to navigate through your website much faster. Moreover, Memcached "refreshes" its cache if any information in the database is edited, so the visitors will never see old data.