what are ratchets
Figure 1: A ratchet featuring gear (1) and pawl (2) mounted on base (3). A ratchet is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. Though something of a misnomer, ratchet is also often used to refer to ratcheting socket wrenches, a common tool with a ratcheting handle.