A system and method are provided which are necessary for exchanging information among a sales agent a1, user a2 and manufacturer A, for preparing a parts check list on an on-line basis, and for storing information to be provided.If, for example, the sales agent a1 or user a2 wants to acquire information from the manufacturer A, manufacturer A will directly confer a password to sales agent a1 with whom manufacturer A directly deals with, while sales agent a1 will directly confer a password to user a2 with whom sales agent a1 directly deals with, on behalf of manufacturer A. This arrangement makes it possible to easily and securely provide, to a specified information seeker, information required by that information seeker.