Drill bits are cutting tools used to create cylindrical holes. Bits are held in a tool called a
drill, which rotates them and provides
torque and axial force to create the hole. Specialized bits are also available for
non-cylindrical-shaped holes.
This article describes the types of drill bits in terms of the design of the cutter. The other end of the drill bit, the shank, is described in the drill bit shank article. Drill bits come in standard sizes, described in the drill bit sizes article. A comprehensive drill and tap size chart lists metric and imperial sized drills alongside the required screw tap sizes.
The term drill can refer to a drilling machine, or can refer to a drill bit for use in a drilling machine. In this article, for clarity, drill bit or bit is used throughout to refer to a bit for use in a drilling machine, and drill refers always to a drilling machine.
The twist drill bit is the type produced in largest quantity today. It drills holes in metal, plastic, and wood.
