Memcached is an open source, high-performance, distributed memory caching system intended to speed up dynamic web applications by reducing the database load. It is a key-value dictionary of strings, objects, etc., stored in the memory, resulting from database calls, API calls, or page rendering.

Memcached was developed by Brad Fitzpatrick for LiveJournal in 2003. However, it is now being used by Netlog, Facebook, Flickr, Wikipedia, Twitter, and YouTube among others.

The key features of Memcached are as follows −

• It is open source.

• Memcached server is a big hash table.

• It significantly reduces the database load

• It is perfectly efficient for websites with high database load.

• It is distributed under Berkeley Software Distribution (BSD) license.

• It is a client-server application over TCP or UDP.

Memcached is not −

• a persistent data store

• a database

• application-specific

• a large object cache

• fault-tolerant or highly available