what is Russian Roulette.

Russian roulette (Russian: Русская рулетка) is a potentially lethal game of chance in which participants place a single round in a revolver, spin the cylinder, place the muzzle against their head and pull the trigger. ‘Russian’ refers to the country of origin of the game and roulette to the element of risk taking and the spinning of the revolver’s cylinder being reminiscent of the spinning of the roulette wheel. The form of the game can be as varied as the participants or their motives (displays of bravado, suicide etc.), but typically a single round is placed in a six-shot revolver resulting in a 1/6 (or approximately 17%) chance of the revolver discharging the round. The revolver’s cylinder can either be spun again to reset the game conditions, or the trigger can be pulled again. Using revolvers with fewer chambers (typically five) or increasing the number of rounds are other variations that increase the risk.

http://en.wikipedia.org/wiki/Russian_roulette