A gate fastening is a device used to secure a gate or door. The most common type of gate fastening is a LATCH, which is a mechanical fastener that is used to hold two objects together. A LATCH typically consists of a bar or loop that is attached to the gate or door and a catch that is attached to the frame. When the LATCH is closed, the catch holds the bar or loop in place, preventing the gate or door from opening.