The present disclosure relates to an encoder and an encoding method thereof, as well as a decoder and a decoding method thereof, which can be used to reduce the number of wires necessary for data transmission and transmit more data at a faster speed with the same number of wires, thereby improving the efficiency of data transmission. The encoder may comprises two input terminals configured to receive two input signals simultaneously, each input terminal comprises a wire identifying a positive voltage and a wire identifying a negative voltage; and a plurality of output terminals, wherein each output terminal comprises a wire identifying a positive voltage and a wire identifying a negative voltage, a combination of the two input signals corresponds to one of the plurality of output terminals, and the output terminal to which the current combination of the two input signals corresponds is configured to output signals through the two wires of the output terminal.