A display device including a display; a first external device interface configured to receive an image signal and an audio signal output from a first external input device; a second external device interface configured to receive an image signal and an audio signal output from a second external input device; and a controller configured to display a graphic user interface including a first external input item describing at least one of the first external device interface and the first external input device connected to the display device via the first external device interface, a second external input item describing at least one of the second external device interface and the second external input device connected to the display device via the first external device interface, a first audio output menu for selecting at least one of a plurality of audio output devices for outputting audio included in the audio signal received from the first external input device, and a second audio output menu for selecting at least one of a plurality of audio output devices for outputting audio included in the audio signal received from the second external input device.