A socket wrench is a tool used to tighten or loosen nuts and bolts. It consists of a handle and a socket that fits over the fastener. The socket is designed to grip the sides of the nut or bolt, allowing for better torque and reducing the risk of stripping the fastener. Socket wrenches come in various sizes to accommodate different fastener sizes. They are often part of a larger set that includes multiple sockets and extensions. This versatility makes them popular in automotive repair, construction, and general maintenance tasks, where quick and efficient fastening is essential.