An image display device is an apparatus having a function of displaying an image that may be watched by a user. The user may watch broadcasting through the image display device. The image display device displays broadcasting selected by the user among broadcasting signals transmitted from a broadcasting station on a display. Broadcasting currently tends to be changed from analog broadcasting into digital broadcasting.
Digital broadcasting means broadcasting of transmitting a digital image and a voice signal. The digital broadcasting is stronger against external noise than the analog broadcasting so that loss of data is small, that it is advantages to correcting errors, that resolution is high, and that a clear screen is provided. In addition, unlike in the analog broadcasting, a bidirectional service may be provided in the digital broadcasting.