Counter-Strike is a first-person shooter video game developed by Valve Corporation. It was initially developed and released as a Half-Life modification by Minh "Gooseman" Le and Jess "Cliffe" Cliffe in 1999, before Le and Cliffe were hired and the game's intellectual property acquired. Counter-Strike was first released by Valve on the Microsoft Windows platform in 2000. The game later spawned a franchise, and is the first installment in the Counter-Strike series.