Steam is a digital distribution, digital rights management, multiplayer and communications platform developed by Valve Corporation. It is used to distribute a large number of games and related media entirely over the Internet, from small independent efforts to larger, more popular games.
Steam is set apart from similar services primarily by its community features, completely automated game update process, and its use of in-game functionality.
There are over 1,100 games available through Steam, and in January 2010 Valve announced that it had surpassed 25 million active user accounts. It regularly services in excess of two million concurrent users.
Steam allows users to purchase computer games entirely digitally. Instead of receiving a box, disc, or even CD key, purchased software is immediately and permanently attached to the user’s Steam account. Content can be downloaded from Steam servers an unlimited number of times to any number of Internet-connected computers that have the Steam client installed.
To play, you launch the game from the client’s built-in list of currently installed games. Steam provides a server browser for users to search, filter, bookmark, and join Internet and LAN servers for games that integrate with it. It can be accessed from the desktop and from an integrated game’s menu system, and queries friends to show a list of servers to which a user’s contacts are connected.