Cam locks, also known as cam fasteners, are a two-piece system that helps hold cabinets together. A cam post threads through the two pieces of wood you are joining together and the cam lock, or cam nut, goes attaches to the end of the cam post and turns to lock everything in place. They make cabinets and furniture easy to assemble while not taking away from the overall aesthetic.
Another type of cam lock can be used to secure cabinet doors with a latch. They require a key to unlock.