A bench grinder is a versatile tool commonly used in workshops for sharpening, shaping, and polishing metal objects. It consists of a motor that spins two grinding wheels, allowing users to grind various materials, such as steel and aluminum. Bench grinders are essential for tasks like sharpening tools, removing rust, and preparing surfaces for welding. These machines come in different sizes and wheel types, including grit wheels for rough grinding and polishing wheels for finishing. Safety features, such as eye shields and spark guards, are important to protect users from debris and sparks generated during operation.