Patent ID: 8433561

Claim:
A printer comprising: a letter string input unit that inputs letter string data consisting of plural letters as to-be-printed target; a print control unit that is operated in response to letter string data being inputted by the letter string input unit as to-be-printed target; a print unit that prints the inputted letter string on a printing medium in response to the print control unit; a storage unit that stores registered letter string data including a specific letter string; a detector unit that detects registration-target letter string data to be stored in the storage unit from the inputted letter string data in response to the print control unit; and a registration unit that registers the registration-target letter string data detected by the detector unit into the storage unit as the registered letter string data in accordance with a predetermined condition, wherein the printer further comprises: a divider unit that divides the registration-target letter string data into specific letter string data corresponding to the specific letter string and additional letter string data is added to the specific letter string data; a judgment unit that judges if the registration-target letter string data and a combination of the specific letter string data and the additional letter string data are identical, based on a registered letter string stored in the storage unit; and a registration control unit that controls the registration unit so as to, in response to a judgment result obtained by a judgment unit, change registration rules for storing registration-target letter string data in the storage unit.