Memcache

Memcached Config For Drupal On Ubuntu

Memcached is a free & open source, high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load

Memcached is used in Drupal mostly for caching Database queries in memory to improve authenticated user experience and reduce load on database. Primarily cache tables are swapped to have a memcached backend.