When the CPU 4202 is supplied with an instruction from an input unit 4207 operated by the user, such as a keyboard, mouse or the like via the input/output interface 4211, it executes the program stored in a ROM (read-only memory) 4203. [0373] Alternatively, the CPU 4202 loads, into a RAM (random-access memory) 4204 for execution, a program stored in the hard disc 4205, a program transferred from a