A jig is a tool that is used to secure a workpiece or machine part on a workstation. It is attached to CNC machine tools, such as a lathe cutting tool, and controls the location and motion of the tool. That is to say, it acts as a guide for such machining equipment. Jigs are special in that they cause the tool to become immobile when they move.

A fixture, also known as a CNC fixture, is a popular CNC machining tool used to provide stability, support, and positioning. It functions in the same way as the jig in that it secures, supports, or mounts a workpiece on a CNC machine.

Jigs and fixtures are used to hold workpieces and machine parts in place. However, there is a distinction between the two. Turning, milling, grinding, slotting, and other multidimensional operations are all possible with these fixtures. Jigs, on the other hand, are ideal for one-dimensional operations such as counterboring, tapping, drilling, and reaming.