To reduce an operator's burden of repeated input of character information of the same content.

A field name, "Your address" of a character input field 3-e displayed on a screen 3-a of an image display device and character information, "Kawasaki City, Kanagawa Prefecture" input into the character input field are associated and stored in a database. When an operator positions a cursor on a character input field to specify it, the field name of the character input field is captured, and the database is searched for a field name equal or similar to the field name of the character input field. If an equal or similar field name is found, the corresponding character information is read from the database and displayed to the operator. If there are a plurality of pieces of character information, the operator selects one and, if necessary, edits and enters the character information, which is input into the specified character input field.