The Start/Pause button (just called the Start button on the Nintendo 64 controller) refers to the small, gray button in the center of a GameCube controller, or the small, red button in the center of a Nintendo 64 controller. It is used on both consoles to pause most games, and select features in the menus. In Melee's trophy gallery, the Start/Pause button is also used to change the background.
Players may repeatedly press the Start/Pause or + button to distract the other players, or to disrupt their combo timing, though is considered very rude. To prevent this, pausing may be turned off.