An appliance which is connectable via an upper portion and/or via a lower portion to at least one external appliance to form a plurality appliances stacked on top of each other, the appliance comprising: a transceiver; and a processor configured to: based on the at least one external appliance being connected to the appliance, identify position information of the appliance based on connecting disposition direction of the at least one external appliance, characterized in that the processor further configured to: control the appliance to perform as a master device based on identifying whether the appliance is arranged at a certain position from among entire connected appliances, and request a control authority to all of the at least one external appliance connected to the appliance, control the appliance to perform as a slave device based on identifying that one of the the at least one external appliance is connected to the upper portion of the appliance, based on the appliance receiving user input while the appliance is performing as the master device, control the transceiver to transmit a control signal to perform an operation corresponding to the user input to all of the at least one external appliance connected to the appliance based on the control authority received from all of the at least one external appliance, wherein the certain position is the highest position from among the entire stacked appliances. a transceiver; and a processor configured to: based on the at least one external appliance being connected to the appliance, identify position information of the appliance based on connecting disposition direction of the at least one external appliance, characterized in that the processor further configured to: control the appliance to perform as a master device based on identifying whether the appliance is arranged at a certain position from among entire connected appliances, and request a control authority to all of the at least one external appliance connected to the appliance, control the appliance to perform as a slave device based on identifying that one of the the at least one external appliance is connected to the upper portion of the appliance, based on the appliance receiving user input while the appliance is performing as the master device, control the transceiver to transmit a control signal to perform an operation corresponding to the user input to all of the at least one external appliance connected to the appliance based on the control authority received from all of the at least one external appliance, wherein the certain position is the highest position from among the entire stacked appliances. based on the at least one external appliance being connected to the appliance, identify position information of the appliance based on connecting disposition direction of the at least one external appliance, characterized in that the processor further configured to: control the appliance to perform as a master device based on identifying whether the appliance is arranged at a certain position from among entire connected appliances, and request a control authority to all of the at least one external appliance connected to the appliance, control the appliance to perform as a slave device based on identifying that one of the the at least one external appliance is connected to the upper portion of the appliance, based on the appliance receiving user input while the appliance is performing as the master device, control the transceiver to transmit a control signal to perform an operation corresponding to the user input to all of the at least one external appliance connected to the appliance based on the control authority received from all of the at least one external appliance, wherein the certain position is the highest position from among the entire stacked appliances. control the appliance to perform as a master device based on identifying whether the appliance is arranged at a certain position from among entire connected appliances, and request a control authority to all of the at least one external appliance connected to the appliance, control the appliance to perform as a slave device based on identifying that one of the the at least one external appliance is connected to the upper portion of the appliance, based on the appliance receiving user input while the appliance is performing as the master device, control the transceiver to transmit a control signal to perform an operation corresponding to the user input to all of the at least one external appliance connected to the appliance based on the control authority received from all of the at least one external appliance, wherein the certain position is the highest position from among the entire stacked appliances.