Abstract: A display apparatus, a control method thereof and a display system having the same are provided. The display apparatus includes: a communication unit; a memory in which the same data as that of an external display apparatus is loaded in the same reference address as that of the external display apparatus; and a controller which controls to change data loaded in a reference address corresponding to address information from the external display apparatus based on data change information from the external display apparatus and to display the changed data if the address information and the data change information are received from the external display apparatus via the communication unit.

Abstract: A video processing apparatus for processing a plurality of video signals, includes: a display; an information storage which stores combination information relating to a combination of two or more video signals, among the plurality of video signals, that can be displayed concurrently on the display; and a controller which controls to display the visual representation of the combination information stored in the information storage on the display.