In the context of a master key system this refers to the very lowest level of key. A change key would typically work a single apartment or a single office door. In the context of a push-button lock or a safe dial, it can refer to a key or tool that is used during the procedure to change the combination. See also master key and submaster key.Cylindrical Lock
This refers to the most common type of modern lockset. The installation involves (among other things) boring a large hole all the way through the door. Most key-in-knob, key-in-lever, and deadbolt locks fall into this category.Control key
This refers to a special key used to remove and install interchangeable cores. Some people also call this a core key.Cylinder
This refers to the lock component where the key is inserted. A typical door knob has one keyhole, therefore one cylinder. Deadbolt locks are available in single-cylinder models and double-cylinder models. A double-cylinder model is operated from both sides with key, while a single-cylinder model uses a key from the outside and has a thumb-turn knob on the inside. Labor charges for rekeying locks is generally per cylinder. Therefore, if a door has a locking door knob and a double-cylinder deadbolt, there are 3 cylinders for the locksmith to service. If you are scheduling rekeying service, it is very helpful to have an accurate cylinder count. This allows us to provide an accurate cost estimate and to schedule ample time for the technician to complete the project.Cam Lock
This is a common type of small lock that is used on cabinets, tool boxes, etc. It is distinguished from other designs by an obvious swing-arm or cam on the back which turns with the key to lock the door or drawer. The lock can be long or short. The cam might be long or short, bent or straight, and may even be in the shape of a hook.