A display apparatus includes: a main information receiver which receives main information; a video processor which processes a main video corresponding to the received main information; a display unit which displays the main video thereon; a sub information communicator which receives sub information comprising at least one of a video, an audio and text through Internet Protocol; and a controller which controls the video processor to process a sub video corresponding to the sub information received through the sub information communicator and display the sub video on the display unit.