PURPOSE: To prevent a processing from becoming complicated by providing the program with unified means for outputting and inputting information to be accumulated and exchanged and a means controlling the security of information.

CONSTITUTION: When the program 11 declares the output system of information and security control information and outputs information, an encoder 30 generates storage type information 22 from an output system, converts information into normalization information in accordance with storage type information, stores it in an information accumulation exchange area 20 and stores storage type information 22 with ciphering information 24 in the information accumulation exchange area 20. If security control information obtained by decoding ciphering information by a prescribed ciphering device and security control information which the program 12 declares are referred and they coincide when the program 12 requests the input of information, normalization information stored in the information accumulation exchange area is converted in accordance with storage type information and an input system while it is inputted to the program 12. Thus, the processing when information is accumulated and exchanged between multiple different programs is prevented from becoming complicated.