A display apparatus includes a first signal transmission device provided with a first video cable configured to selectively transmit a first image signal transmitted by a first method and a second image signal transmitted by a second method, an audio cable configured to transmit a sound signal, and a first output connector connected to the first video cable and the audio cable; a second signal transmission device provided with a second video cable configured to transmit a third image signal transmitted by the second method, and a second output connector connected to the second video cable.