High-Speed Steel—The most versatile taps resist heat and wear to stay sharp. They’re good for most metals and plastic.

Uncoated—The economical choice, these won't last as long as coated taps.

Taper Chamfer—Good for both starting holes and threading through holes. These taps have the longest taper to gradually engage with the material, reducing the force needed to turn them. They can't reach the bottom of blind holes, however, so you will likely need to finish with a bottoming-chamfer tap.

Plug Chamfer—These taps thread through holes and blind holes. The tapered section is shorter than a taper chamfer and longer than bottoming chamfer. As a result, they're easier to turn than bottoming taps but require more force than taper taps.

Bottoming Chamfer—Cut all the way to the bottom of blind holes with taps that have the shortest taper. Since these require the most force to turn, they’re often used to finish holes started by taper- or plug-chamfer taps.

Number of Flutes—Taps with fewer flutes have more space to capture chips, so you won’t have to clear them as often. However, they can be more difficult to keep straight in the hole.