A user operation log storing apparatus for investigating operations performed by a user, types of data handled by the user and contents of processing conducted by the user, and for saving acquired information through the investigation. The present invention provides a group of objects (VOs) for a user to access the WWW, database, etc. and conduct communications and for a service provider to readily compare and analyze acquired data. The VOs respectively hold as a log file an attribute thereof, results of user actions and an attribute value of a slot via which the VOs exchange data. The log files are sent to the server on the network, where they are classified according to users and stored in a time-series manner. Using the saved log file, the present invention also provides an environment as a VO for analyzing and utilizing the user's operation log.