The present invention relates to a simulator, and more particularly, to a simulator in which two cylinders move in the left, right, forward, and backward directions, or in a combination of the left, right, forward and backward directions by the driving force of a single compressor having a small capacity to enable a user to enjoy a sports game, a combat game, or the like with a realistic feeling. As described above, the present invention has a simple configuration and enables a user to feel the graphical representation on a computer as if he/she is a part of the computer game representation, thus creating a new game culture.