A hammer is a handheld tool characterized by a heavy head, usually made of metal, mounted on a long handle, typically made of wood, metal, or fiberglass. Hammers are primarily used for driving nails, fitting parts, forging metal, and breaking objects apart. They come in various shapes and sizes, each designed for specific tasks. Common types of hammers include claw hammers, ball-peen hammers, sledgehammers, and mallets. Hammers are widely utilized in construction, woodworking, metalworking, and other trades, making them essential tools in many industries and household settings.