To solve a problem that it is difficult for the conventional electronic mail display editing device to understand the contents of a received mail from only the subject when the number of electronic mails is large, and whether or not the mail is important for himself is judged with delay when the contents of the mail text are long, so that the response mail is delayed.

The subject of a received mail is designated, and the summary is displayed. Also, the list of the summaries of unread mails is displayed so that a responding operation to the received mail can be executed according to the display of the summary. Thus, it is possible to shorten a mean processing time required for understanding the contents of the received mail or the responding work.