Valve Corporation

Valve Corporation (commonly referred to as Valve) is an American video game developer and digital distribution company headquartered in Bellevue, Washington. The company is known for the Half-Life, Counter-Strike, Portal, Day of Defeat, Team Fortress, and Left 4 Dead series, Dota 2, and its software distribution platform Steam.

After the success of Half-Life, the team worked on mods, spin-offs, and sequels, including Half-Life 2. All current Valve games are built on its Source engine. The company has developed six game series: Half-Life, Team Fortress, Portal, Counter-Strike, Left 4 Dead and Day of Defeat. Valve is noted for its support of its games’ modding community, most prominently, Counter-Strike, Team Fortress, and Day of Defeat. Valve has branched out with this tradition to continue developing Dota 2 as the standalone sequel to the Warcraft III mod.Each of these games began as a third-party mod that Valve purchased and developed into a full game. They also distribute community mods on Steam.Valve announced the Source 2 engine in March 2015, later porting the entirety of Dota 2 to the engine in September of that year

Cancelled games

Incomplete games include a fairy-themed role-playing gameProspero and Stars of Blood.

Valve worked with Arkane Studios on The Crossing, which was canceled in May 2009. Arkane later tried to produce Return to Ravenholm (a.k.a. Half-Life 2: Episode Four) without consensus by Valve, which was then also canceled