What is the deadbolts lock?
The most common type of bolt is a basic single cylinder bolt that operates through the knob on the inside of the door and the keyhole on the outside. The bolt is "dead" because you have to manually move it in and out with a key or knob. If the entrance door has a glass panel, it can still be destroyed because the intruder can break the glass and open the latch from the inside.
If you have a two-cylinder bolt, the intruder will not be able to enter the door through the broken glass panel. This is the safest type of bolt because it requires a key to operate on both sides of the door. Some people do not like to use a two-cylinder bolt because of the safety of leaving home in the event of a fire. If the latch is in the locked position, the key exit is required, which may prevent a quick exit or attention when the key is lost. If you do choose to use the two-cylinder tongue system, move the key close to the door area, but not near the door area. It is important to note that before selecting the bolt, it is important to know that some fire safety and building codes prohibit the installation of locks that require the key to open the door from the inside.