A word processing system for inserting characters into a series of displayed characters within a predetermined field, including a circuit (1008) for moving a series of characters displayed on and after a cursor position to the end portion of the field by pushing an insertion key indicating the insertion of characters, a circuit (1015) for inserting a character into the cursor position and moving the cursor by pushing a character key, and a circuit (1017) for filling the spaces following the inserted characters with the previously moved series of characters.