A display device with less power consumption. The display device operates in a still image display period and a moving image display period, and includes a receiving circuit having a function of receiving an image signal, a driver circuit having a function of driving a display portion, and the display portion having a function of displaying an image. The display portion displays an image at a frame frequency of less than or equal to 1 Hz in the still image display period. The receiving circuit stops receiving an image signal in the still image display period. Switching from the still image display period to the moving image display period is accurately performed by an external signal.