Disclosed is a washing machine capable of changing program and solving a fundamental problem of malfunction. The washing machine includes: a storage tank mounted vertically or horizontally for storing washing water; an inner tub mounted vertically or horizontally inside the storage tank in a rotatable manner; a load part including a motor for rotating the inner tub, water supply means for supplying water and drain means for draining water; a drive micom for controlling the load part; a key input part for allowing a user to input various operation orders or to set functions of the washing machine; a display part for displaying the functions and operation conditions; a memory capable of reading and writing and for storing operation algorism of the washing machine and information related with the washing machine; an interface part for inputting and outputting data with an external device; and a system micom for controlling the drive micom for performing a washing operation corresponding to the user's operation order through the key input part, controlling the display part for displaying the corresponding operation condition or function and storing data transferred from the external device through the interface part into the memory. The washing machine can maximize convenience, washing performance and operational efficiency.