There are several different styles of switchblade knives. Out the front or OTF knives refer to the blade deployment function.
Whereas most switchblades have the blades fire from the side …OTF blades fire straight out the top of the knife.
The blades slide on a tract inside the handle & come in either single action or double action.
Single action OTFs fire with the push of the trigger & have to be manually retracted usually by pulling back on a “charging handle” type mechanism.
Double action OTFs deploy & retract both via the trigger, and push forward to fire & pull back to retract.