Does all the above
A jig is a work-holding device that holds, supports, and locates the workpiece and guides the one or more tools to perform a specific operation.
A fixture is a work-holding device that only holds, supports, and locates the workpiece, but does not guide the tools to perform a specific operation.
Drilling, reaming, taping and other allied operations
Drill jigs are used for drilling, reaming, taping and other allied operations.
Holds and locates the workpiece
Fixtures are the work holding devices, which holds, supports and locates the workpiece but not guides the cutting tool to perform a specific operation.
Post jig
Post jigs are used for location from a bore.
Plate jig
Plate jigs are sometimes made with legs to raise the jig off the table for large work.
Plate jigs mainly consist of a single bush plate with a provision for location and the clamping of workpiece. So the drill bushes guide the drills.
