Half-Life is a series of first-person shooter games developed and published by Valve, beginning with the original Half-Life, released for Windows in 1998. The earliest known canceled Half-Life game dates to 1999. Between Half-Life 2: Episode Two (2007) and Half-Life: Alyx (2020), Valve canceled at least five Half-Life games, including Half-Life 2: Episode Three, a version of Half-Life 3, and games by the studios 2015, Inc., Junction Point Studios and Arkane Studios.