How do door handles work?

A door handle controls the door using the manipulation of a latch. It is a mechanical fastener that allows two or more objects to allow the door to be pulled using a rotating mechanism. When the same is pulled, the handle gets rotated in a clockwise or anticlockwise direction to give adequate orientation.
When the handle is turned, the square spindle inside the mechanism turns. It leads to the movement of the cylinder that is connected with a latch bolt to keep the door closed. When the same turns, the latch bolt is turned and withdrawn into the door to open it.