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 or sharpen tools like chisels and blades. Bench grinders are essential for maintaining the edges of cutting tools and can also be used for removing rust or smoothing rough surfaces. These machines come in various sizes and can be equipped with different types of wheels, such as grit wheels for sharpening and wire wheels for cleaning. Safety features, like eye shields and spark guards, are important to protect users from debris and sparks during operation.