SUCCESSIVE INDEX MECHANISM

PROBLEM TO BE SOLVED: To provide an efficient access means for desired information stored in a file in a large-scale data base like the worldwide web of the Internet or an intranet. SOLUTION: A successive index mechanism 123 is provided to apply indexes inclusively and successively to information stored in information sources, thereby a user quickly retrieves the position of desired information by using the index. For the above purpose, the successive index mechanism 123 includes an index constitution element 412 like a key word featuring a title of information and a corresponding position element 411 (e.g. URL) for discriminating which file includes the title featured by the corresponding index constitution element 412. The successive index mechanism 123 retrieves all files to generate inclusive indexes of information in this file system 165 and updates the indexes at predetermined intervals or intervals that the user specifies.