Classification of electric grinders used for metalworking, deburring, and grinding operations in manufacturing sites. Portable electric tools including angle grinders, straight grinders, and disc grinders that mount rotating grinding wheels or discs for cutting, grinding, and polishing materials. Suitable for weld bead removal, casting deburring, metal surface finishing, and cutting operations. Distinguished from stationary grinding machines and large grinding equipment, limited to handheld electric tools operated by workers. Includes both corded and cordless types, frequently used in production line work and maintenance operations.