Archaic. Old. There is a cut off valve so gas does not escape when there is no flame to burn it. In theory, if the flame goes out for any reason the gas cuts off so you do&n8#217;t end up bright red and dead on the kitchen floor. With old stoves (like mine) this valve has the oven equivalent of memory loss. So it turns the gas off when you want it on. Which is why it is necessary to hold the knob in while you hold a lit match to the gas, trying to bypass the wonky cut off valve.
