Backset: The distance from the edge of the door to the center of the hole drilled for the door hardware. Most backsets are 2 3/8" or 2 3/4". View information on Determining Backset and Door Hardware Installation Instructions which includes an installation template for both 2 3/8 and 2 3/4 backsets.
Deadbolt: A deadbolt or dead lock, is a locking mechanism which cannot be moved to the open position except by rotating the lock cylinder. The more common spring bolt lock uses a spring to hold the bolt in place, allowing retraction by applying force to the bolt itself. A deadbolt therefore makes a door more resistant to entry without the correct key. A deadbolt is often used in conjunction with a spring-bolt lock on an entry door to a building.
Mortise Lock: A mortise lock is one that requires a pocket or mortise to be cut into the door or piece of furniture into which the lock is to be fitted. Mortise locks are generally found on older buildings constructed before the advent of bored cylindrical locks, but they have recently become more common in commercial and upscale residential construction in the United States.