Highly visible and used on a daily basis, doorknobs and locks are critical to a home's appearance and convenience and they provide the first line of defense against intruders.
In the construction trade, doorknobs are sometimes called locksets. The type on interior doors may be called passage locksets, spring-latch locks, interior knobs or tubular locks. If one of the knobs has a push-button lock, it's generally called a privacy lock. This is the type found on bathroom and some bedroom doors.
Locksets for exterior doors may be called entry locksets, keyed locks or exterior locks. A key-operated lock that has no door knob or lever is called a deadbolt lock. Entry locksets can be locked or unlocked from both sides of the door, using a key, a button or a throw latch, depending upon the type.
Lockset bodies are classified as either cylindrical or mortise. Cylindrical locksets have a rounded body designed to fit into intersecting holes bored in a door. Mortise locksets, shown here, have a large, rectangular body that slides into a mortise cut into a door's edge. With a mortise set, the knob is generally interconnected with a deadbolt.
