Abstract: A message sending and reception optimizing method using a sender's end information processing apparatus disposed on a sender's end of a message and a recipient's end information processing apparatus disposed on a recipient's end of the message has a step of determining an optimum form of message sending and reception while considering convenience of a sender and/or a recipient by communicating predetermined information between the sender's end information processing apparatus and the recipient's end information processing apparatus before performance of the message sending and reception.

Abstract: The customer information utilization system of the present invention includes history acquisition units, history storage units, and history utilization units. The history acquisition units are arranged in each device belonging to users and acquire history information relating to the history of use of the devices. The history storage units collect history information relating to the history of use of each device belonging to the users by way of the history acquisition units and store the history information. When a product or service is to be provided or when an application is to be executed, the history utilization units use appropriate history information of the history information relating to the history of use of each device belonging to the users to produce customer information that is to be utilized in the product, service or application.