Half-Life

Half-Life  is a 1998  first-person shooter  (FPS) game developed by  Valve  and published by  Sierra Studios  for  Windows . It was Valve's debut product and the first game in the  Half-Life  series . Players assume the role of  Gordon Freeman , a scientist who must escape the  Black Mesa Research Facility  after it is invaded by aliens. The  gameplay  consists of combat, exploration, and puzzle-solving. Valve was disappointed with the lack of innovation in the FPS genre, and aimed to create an immersive world rather than a "shooting gallery". Unlike other games of the time, the player has almost uninterrupted control of the  player character , and the story is told mostly in  scripted sequences  rather than  cutscenes . Valve developed using  GoldSrc , a heavily modified version of the  Quake  engine , licensed from  id Software . The  science fiction  novelist  Marc Laidlaw  was hired to shape the story and assist with design. Half-Life  received acclaim for its graphics, gameplay and narrative, and won more than 50  PC  " Game of the Year " awards. It is considered one of the most influential FPS games and one of the  greatest video games ever made . By 2008, it had sold over nine million copies. It was followed by the  expansion packs   Opposing Force  (1999) and  Blue Shift  (2001), developed by  Gearbox Software . It was ported to the  PlayStation 2  in 2001, along with the multiplayer expansion  Decay , and to  OS X  and  Linux  in 2013. Valve ported  Half-Life  to its  Source  engine as  Half-Life: Source  in 2004. In 2020, Crowbar Collective released an unofficial remake,  Black Mesa . Half-Life  inspired numerous fan-made  mods , some of which became standalone games, such as  Counter-Strike ,  Day of Defeat  and  Sven Co-op . It was followed by  Half-Life 2  (2004),  Half-Life 2: Episode One  (2006),  Half-Life 2: Episode Two  (2007) and  Half-Life: Alyx  (2020).