COMMUNICATION TERMINAL DEVICE

PROBLEM TO BE SOLVED: To provide a communication terminal device in which a device function can easily be expanded. SOLUTION: A CPU 101 controls the operation of the entire device. A ROM 102 in which a program of a browser, etc., is stored and a RAM 103 used as a working area, etc., are connected to the CPU 101 through a memory bus 104. A STB 100 has a modem part 105 for being connected to the Internet through a telephone line. The image and sound data of each Web page acquired from a prescribed Web site of the Internet are processed by an AV processor 108, and the image is displayed and the sound is outputted by using a television receiver 121. The STB 100 has an external connection terminal 110 connected to the memory bus 104. An expansion device, e.g. a player for MP3 reproduction, etc., can be connected to the terminal 110 so that function expansion can easily be performed.