In May 2006, Valve announced a trilogy of episodic games that would continue the Half-Life 2 story, with the final episode planned for release by Christmas 2007.

Half-Life 2 was the first game to use Valve's Steam content delivery system, a system that eventually led to Valve falling out with publisher Sierra Entertainment. Considered one of the greatest video games of all time, the game has been critically praised for its advances in computer animation, sound, narration, computer graphics, artificial intelligence and physics. Half-Life 2 garnered near-unanimous positive reviews and received critical acclaim much like its predecessor, winning over 35 Game of the Year awards for 2004. The G-Man inserts Freeman into City 17 in Eastern Europe to combat the Combine occupation. Set twenty years after the original game, Earth has been occupied by the Combine, a transdimensional race that exploited the events of the first game to invade. Half-Life 2 returns the player to the role of Gordon Freeman. The game had a six-year development cycle, which saw several delays and the leak of the game's source code. On November 16, 2004, Valve released Half-Life 2. Set before Half-Life 2, players control Freeman's ally Alyx Vance in her quest to defeat the alien Combine. In 2020, after years of speculation, Valve released its flagship virtual reality game, Half-Life: Alyx. Over the following decade, numerous Half-Life games were canceled, including Episode Three, a version of Half-Life 3, and games developed by Junction Point Studios and Arkane Studios. The first game in the Portal series, set in the same universe as Half-Life, was released in 2007.

It was followed by the extra level Lost Coast (2005) and the episodic sequels Episode One (2006) and Episode Two (2007). In 2004, Valve released Half-Life 2 to further success, with a new setting and characters and physics-based gameplay. Half-Life was followed by the expansions Opposing Force (1999), Blue Shift (2001) and Decay (2001), developed by Gearbox Software. The innovative scripted sequences were influential on the FPS genre, and the game inspired numerous community-developed mods, including the multiplayer games Counter-Strike and Day of Defeat.

Players control Gordon Freeman, a scientist who must survive an alien invasion. The original Half-Life, Valve's first product, was released in 1998 for Windows to critical and commercial success. The games combine shooting combat, puzzles and storytelling. Half-Life is a series of first-person shooter (FPS) games developed and published by Valve.

Half life 1 free