Lock and key

The utility model provides a lock and belongs to the field of locks. The lock comprises a lock outer shell, the lock outer shell comprises a front end outer shell and a rear cover, and the front end outer shell and the rear cover are detachably connected to form a cavity. A sliding block and a spring bolt are arranged inside the cavity. While the functions of the lock are achieved, the internal structure of an existing lock is greatly simplified, and the functions of the lock are achieved through cooperation of the sliding block and the spring bolt connected with the sliding block in a sliding mode. In this way, the problem that because the internal structure of the existing lock is complex, the overall size of the lock is large is solved.