Professional Counter-Strike competition involves professional gamers competing in the first-person shooter game series Counter-Strike. The original game, released in 1999, is a mod developed by Minh "Gooseman" Le and Jess Cliffe of the 1998 video game Half-Life, published by Valve. Currently, the games that have been played competitively include Counter-Strike (CS also called CS 1.6), Counter-Strike: Condition Zero (CS:CZ), Counter-Strike: Source (CS:S) and Counter-Strike: Global Offensive (CS:GO). Major championships began in 2001 with the Cyberathlete Professional League Winter Championship, won by Ninjas in Pyjamas.
