Takeoff/Go-around switches (TO/GA) are switches activated on the autothrottle of an autopilot of a modern aircraft. It has two modes, takeoff (TO) and go around (GA). The switch is the same for both takeoff and go around modes. Usually on approach to land the autopilot will be set to approach mode on the autopilot therefore if the TO/GA switch is pressed it will activate the go around mode. The TO/GA switch is near the throttle levers on Boeings. On Airbuses it is activated by pushing thrust levers fully forward to TOGA detent.
Some aircraft make the TO/GA switch to command the autopilot to fly a missed approach pattern, if the autopilot is programmed to do so. The TO/GA switch can be used even after touchdown if reverse thrust has not been selected.