Drill

A drill is a power tool used to make holes in materials such as wood, metal, masonry or plastic. Its main working part is a rotating drill bit held in a chuck. When the motor turns the chuck, the bit rotates and its cutting edges remove material from the surface. Different bits are designed for different materials and hole sizes.

Many drills allow the user to change the rotation speed or direction, while some models also have a hammer function that produces rapid impacts along the axis of the bit. Corded drills receive electricity through a cable, whereas cordless models use rechargeable batteries. The motor, gears and other internal parts transfer electrical energy into the mechanical motion needed for drilling.

A drill can also be used with other attachments for tasks such as driving screws or polishing, depending on the model and accessory. During drilling, the bit must stay aligned with the intended hole, while the tool's body provides the grip and control needed to guide the movement. Friction between the bit and the material produces heat, so excessive pressure or an unsuitable bit can reduce efficiency and damage the tool or workpiece.

The type of material determines the appropriate bit, speed and technique. A drill therefore combines principles of electricity, mechanics and materials science: electrical energy powers a motor, the motor creates rotation, and the rotating bit transfers force to remove material. Because rotating parts can cause injuries, drills should be used with appropriate safety precautions and according to the manufacturer's instructions.