By moving his or her arms through the water the swimmer creates a thrust force that propels the swimmer forward. For a swimmer moving at constant speed through the water the thrust force is equal to the drag force. The drag force is created by the motion of the swimmer through the water. This force resists the motion of the swimmer through the water. A drag force exists any time an object moves through a fluid, such as air or water. The faster an object moves through a fluid the greater the drag force. The drag experienced by a swimmer swimming at the surface can be broken down into three components: (1) Pressure drag (form drag) - this is due to the swimmer "pushing" the water out of the way as he swims along, (2) Skin Friction drag - this is due to the friction between the water and the swimmer's body as the water flows over it. This type of friction occurs inside the very thin layer of water directly touching the swimmer's body, (3) Wave drag - this is drag due to the surface waves produced by the swimmer as he swims along. Special body suits produced by Speed serve to reduce skin friction drag allowing swimmers to swim faster.