Rekeying a lock means replacing the working key of the lock with a different key. This is all done without changing the lock itself. In simpler words, you keep the same lock but the old key will no longer work on it. This is completed by taking the lock apart and changing some of the parts inside called “tumblers” or “key pins”.
The key pins in your lock have a sequence that corresponds to a specific key. Therefore, when you replace those pins with different ones, you essentially set a new key that will now operate the lock. This may sound complicated, however, it’s an easy procedure given the right tools for rekeying the lock.