The cylindrical part that rotates within the cylinder when the key is turned. The keyway (the slot where the key is inserted) is part of the plug.
Standard pin-tumbler locks use a series of small pins of varying lengths. When the right key is inserted, the "teeth" of the key push these pins up to a specific height called the Shear Line . diagram of a door lock
Here are three distinct types of "interesting papers" regarding door lock diagrams, depending on what specifically catches your interest: The cylindrical part that rotates within the cylinder
This is where the magic—and the security—happens. If you were to look at a cross-section diagram, you would see these moving parts: When the right key is inserted, the "teeth"
| Part | Function | |------|-----------| | | Manual mechanism to retract the latch without a key. | | Interior Cylinder (on double-cylinder locks) | Requires a key even from inside (used on security doors). |