To make easier communication using electronic mails, and to provide a new communication tool by applying the communication using electronic mails to business processes.

According to a request from a business-side member, a mail server 82 transmits an electronic mail to a customer-side information terminal 3 via the Internet 2, the mail including a specific question content 41 and an answer content 42 to the question content 41. The electronic mail includes a command statement for sending the answer content 42 when a send button is clicked on the customer-side terminal 3. The command statement is one for executing a CGI program 811 on a WWW server 81, or one for sending the answer content 42 to the mail server 82. Data of the sent answer content 42 are saved in an answer DBF 833 or an answer mail DBF 834 in a DBS 83 and are turned into databases.