A screwdriver is a tool used to turn (or "drive") screws into something. It has an axial shaft with a tip of a certain shape that fits into the head of a screw. On the other end of the screwdriver is a cylindrical handle to be held by a person's hand. As the handle is rotated, it creates a torque that turns the tip via the screwdriver's shaft. There are many different sizes and kinds of screwdrivers. A screwdriver is usually identified by the shape of its tip. The tip is shaped in a certain way to match the groove cut into the head of a screw. A screwdriver is, therefore, a mechanism to apply torque to a screw and turn it in tight spaces.