A smart controlling device for processing data according to a voice recognized using artificial intelligence, comprising: a receiver configured to receive an input comprising a command trigger; a signal outputting unit configured to transmit a control command associated with a plurality of external display devices; and a controller configured to: select a display device among the plurality of external display devices; cause a power status of the selected display device to be changed to a power-on status; and cause a response data corresponding to a first command data received after the command trigger to be output on a display of the selected display device, wherein the selected external display device is selected from the plurality of external display devices based on at least an attribute of the first command data, an attribute of the response data, or an attribute of the selected external display device, and wherein the controller is further configured to: detect the power status of the display of the selected display device; and when the power status of the display of the selected display device corresponds to a power-off status, cause the signal outputting unit to transmit a control command to change the power status of the display of the selected display device from the power-off status to a stand-by status. a receiver configured to receive an input comprising a command trigger; a signal outputting unit configured to transmit a control command associated with a plurality of external display devices; and a controller configured to: select a display device among the plurality of external display devices; cause a power status of the selected display device to be changed to a power-on status; and cause a response data corresponding to a first command data received after the command trigger to be output on a display of the selected display device, wherein the selected external display device is selected from the plurality of external display devices based on at least an attribute of the first command data, an attribute of the response data, or an attribute of the selected external display device, and select a display device among the plurality of external display devices; cause a power status of the selected display device to be changed to a power-on status; and cause a response data corresponding to a first command data received after the command trigger to be output on a display of the selected display device, wherein the selected external display device is selected from the plurality of external display devices based on at least an attribute of the first command data, an attribute of the response data, or an attribute of the selected external display device, and wherein the controller is further configured to: detect the power status of the display of the selected display device; and when the power status of the display of the selected display device corresponds to a power-off status, cause the signal outputting unit to transmit a control command to change the power status of the display of the selected display device from the power-off status to a stand-by status. detect the power status of the display of the selected display device; and when the power status of the display of the selected display device corresponds to a power-off status, cause the signal outputting unit to transmit a control command to change the power status of the display of the selected display device from the power-off status to a stand-by status.