Steam is a market-leading leading digital platform created by Valve Corporation.

Before implementing Steam, Valve had problems updating its online games, such as Counter-Strike; providing patches would result in most of the online user base disconnecting for several days. Valve decided to create a platform that would update games automatically and implement stronger anti-piracy and anti-cheat measures. Valve approached several companies including Microsoft, Yahoo!, and RealNetworks, to build a client with these features, but were refused.

Steam’s development began before 2002. Working titles for the product included “Grid” and “Gazelle”. It was first revealed to the public on March 22, 2002, at the Game Developers Conference, where it was presented purely as a distribution network. To demonstrate the ease of integrating Steam with a game, Relic Entertainment created a special version of Impossible Creatures. However, the game was never released on Steam. Valve partnered with several companies, including AT&T, Acer, and GameSpy Industries. The first mod released on the system was Day of Defeat.