PURPOSE: To easily input a special character without executing a complicated operation, by selecting a desired special character, based on a display related to a field of the special character.

CONSTITUTION: When an input of a special character is requested in the course of generating a document, a special character key of an input part 12 is operated. By this operation, an index related to a field of the special character is read out of an input buffer 14 and displayed on a display part 26. When the field to which a desired special character belongs is selected from in this displayed index, the special character belonging to the selected field is read out of a special character storage part 18 and displayed on the display part 26. Subsequently, when the desired special character is selected, the selected special character is inputted to the document, when it is being generated. In this way, the special character can be easily inputted without executing a complicated operation.