Zombies are a real threat to society as we know it. They have been set loose and it's your job to get rid of as many as you can. Move your character around with the arrow keys. Aim your weapon with the mouse, and use the left mouse button to shoot. If you think a different weapon will work better, then go ahead and hit Ctrl to change the weapons. Hurry up though, because society depends on your ability to kill all the zombies.