Taps are used to cut what type of threads?

Taps are specifically designed to create internal threads within a solid material, which allows for the insertion of screws or bolts that can then be secured within a hole. When a tap is rotated into a material, its cutting edges remove material to form a helical groove that corresponds to the desired thread specifications. This process is vital for manufacturing and assembly in a variety of engineering applications, making taps an essential tool for creating threaded holes in components.

The other choices do not accurately describe the function of taps. External threads are created using dies, which are tools designed for that specific purpose, while fine and coarse threads refer to the pitch and design characteristics of threads rather than the type of tool used to cut them. Therefore, internal threads are the correct focus regarding the use of taps.