Valve Software

Valve Corporation (also known as Valve Software or simply Valve) is an American video game development and digital distribution company based in Bellevue, Washington, United States. It was founded in 1996 by former Microsoft employees Gabe Newell and Mike Harrington, and made famous by its highly successful and critically acclaimed first product, Half-Life, released in November 1998. It is also well known for its social-distribution network Steam, and for developing the Source engine, which has been used in every product since its introduction in 2004.

Valve was founded by long-time Microsoft employees Gabe Newell and Mike Harrington on August 24, 1996 as an L.L.C. based in Kirkland, Washington. After incorporation in April 2003, it moved from its original location to Bellevue, Washington, the same city in which their original publisher, Sierra On-Line, Inc., was based.