Counter Strike 1.6 is a tactical FPS game (First Person Shooter) which was developed by Valve and released onto Steam (a loader to hold games onto. It originally was a modification for the game Half-Life but then became so popular that it became separately released with Condition Zero.
Counter Strike 1.6 is a game where the player must pick to be on a terrorist team, counter terrorist team or be a spectator. The objective is to eliminate the opponent by either killing them (shooting), defusing the terrorist bomb (ct only) or saving the hostages (ct only). Each round starts with both teams spawning simultaneously (usually at the opposite end of the map) and then the player will have the chance to buy a weapon of his or her preferance during the freeze time. After a player is killed, he/she becomes a spectator until the next round. Personally i enjoy this game very much and recommend it to any FPS lovers.
I would personally rate this game 9.5/10 because of its use of tactics and skill level required to play substantially, it truely is a hardcore FPS.