A display device comprising: a first touch screen to display a first object; a second touch screen to display a second object; and a controller configured to: receive (S110, S210) a first touch to the first object on the first touch screen, receive (S140, S230) a second touch after receiving the first touch without dragging the first object or a position on the second touch screen, wherein the first touch to the first object is maintained during a time when the second touch to the second object on the second touch screen is received, execute (S180, S250) a function corresponding to the second object by associating the first object to the function corresponding to the second object when the second touch is maintained for a predetermined time, display an execute screen of the function on the second touch screen, wherein the first object in the executing the function is displayed in the first touch screen during the executing the function, wherein the function comprises moving or copying the first object from the first touch screen to a destination position on the second touch screen without dragging the first object to the destination position on the second touch screen. a first touch screen to display a first object; a second touch screen to display a second object; and a controller configured to: receive (S110, S210) a first touch to the first object on the first touch screen, receive (S140, S230) a second touch after receiving the first touch without dragging the first object or a position on the second touch screen, wherein the first touch to the first object is maintained during a time when the second touch to the second object on the second touch screen is received, execute (S180, S250) a function corresponding to the second object by associating the first object to the function corresponding to the second object when the second touch is maintained for a predetermined time, display an execute screen of the function on the second touch screen, wherein the first object in the executing the function is displayed in the first touch screen during the executing the function, wherein the function comprises moving or copying the first object from the first touch screen to a destination position on the second touch screen without dragging the first object to the destination position on the second touch screen. receive (S110, S210) a first touch to the first object on the first touch screen, receive (S140, S230) a second touch after receiving the first touch without dragging the first object or a position on the second touch screen, wherein the first touch to the first object is maintained during a time when the second touch to the second object on the second touch screen is received, execute (S180, S250) a function corresponding to the second object by associating the first object to the function corresponding to the second object when the second touch is maintained for a predetermined time, display an execute screen of the function on the second touch screen, wherein the first object in the executing the function is displayed in the first touch screen during the executing the function, wherein the function comprises moving or copying the first object from the first touch screen to a destination position on the second touch screen without dragging the first object to the destination position on the second touch screen.