Centripetal force keeps a rotating object spinning. . Centrifugal force slings things away from a spinning object. . Put an apple on a lazy susan or phonographic turntable and spin it. When the apple rolls off the LS or turntable, that's centrifugal force. As the LS or turntable keeps spinning, that's centripetal force. . The above is my short answer. The following comes from Wikipedia: The centripetal force is the external force required to make a body follow a circular path at constant speed. The force is directed inward, toward the center of the circle. Hence it is a force requirement, not a particular kind of force. Any force (gravitational, electromagnetic, etc.) can act as a centripetal force. The term centripetal force comes from the Latin words centrum ("center") and petere ("tend towards", "strive for sth."). The centripetal force always acts perpendicular to the direction of motion of the body. In the case of an object that moves along a circular arc with a changing speed, the net force on the body may be decomposed into a perpendicular component that changes the direction of motion (the centripetal force), and a parallel, or tangential component, that changes the speed.