Latch
A latch is a type of hardware that is used to join two objects together. A latch often keeps animals or wind from opening something. This could be a door or a gate. Unlike a lock, a latch is easy to open if you know how, so it can be convenient on a gate that needs to be opened often.
a childproof latch (also called a baby latch) is designed to keep children from opening doors or drawers. They keep children from getting into things such as household cleaners, medicines, matches or knives.
a gate latch is used for outdoor gates. There are a wide variety of types. There are also a number of considerations before choosing a gate latch.
a Touch latch holds a door in the closed position. It releases with a gentle touch on the door.
References
Hardware (mechanical)