My front door hardware has only one lock, a double cylinder dead bolt. The handle portion of the hardware does not have a lock. There are other types of door hardware that have a dead bolt as well as a lock in the door knob. Normally they are used on outside doors other than the main entrance/front door. When buying that type, be sure to get matching key numbers so that one key will operate both locks.
Another important thing to consider is using double cylinder dead bolt locks on outside doors that have glass. That way an intruder cannot gain entrance by breaking the glass, reaching in an unlocking the door by turning the knob. Keep a key hidden close by in order to exit when necessary, but do not leave the key in the lock.
I hope this is helpful.