An operating method of a display device, the method comprising: recognizing, by the display device, a user's function control voice for controlling a function of a peripheral device; controlling, by the display device, the peripheral device to perform a function corresponding to the recognized function control voice in the peripheral device through a remote control device; and providing, by the display device, a control state of the peripheral device representing that the function corresponding to the recognized function control voice is performed in the peripheral device, wherein the controlling of the peripheral device through the remote control device comprises: transmitting, by the display device, a function control command corresponding to the function control voice to the remote control device, and controlling, by the display device, the remote control device to transmit an IR signal corresponding to the function control command to the peripheral device, characterized in that the providing step comprising: outputting information representing that the function of the peripheral device corresponding to the received IR signal is performed if the peripheral device receives the IR signal through the remote control device, and outputting information indicating an operation of the remote control device if the peripheral device does not receive the IR signal through the remote control device. recognizing, by the display device, a user's function control voice for controlling a function of a peripheral device; controlling, by the display device, the peripheral device to perform a function corresponding to the recognized function control voice in the peripheral device through a remote control device; and providing, by the display device, a control state of the peripheral device representing that the function corresponding to the recognized function control voice is performed in the peripheral device, wherein the controlling of the peripheral device through the remote control device comprises: transmitting, by the display device, a function control command corresponding to the function control voice to the remote control device, and controlling, by the display device, the remote control device to transmit an IR signal corresponding to the function control command to the peripheral device, characterized in that the providing step comprising: outputting information representing that the function of the peripheral device corresponding to the received IR signal is performed if the peripheral device receives the IR signal through the remote control device, and outputting information indicating an operation of the remote control device if the peripheral device does not receive the IR signal through the remote control device. transmitting, by the display device, a function control command corresponding to the function control voice to the remote control device, and controlling, by the display device, the remote control device to transmit an IR signal corresponding to the function control command to the peripheral device, characterized in that the providing step comprising: outputting information representing that the function of the peripheral device corresponding to the received IR signal is performed if the peripheral device receives the IR signal through the remote control device, and outputting information indicating an operation of the remote control device if the peripheral device does not receive the IR signal through the remote control device. outputting information representing that the function of the peripheral device corresponding to the received IR signal is performed if the peripheral device receives the IR signal through the remote control device, and outputting information indicating an operation of the remote control device if the peripheral device does not receive the IR signal through the remote control device.