a method and apparatus for discriminating bottle types , for stirring the toner , and for detecting the amount of toner remaining in the toner bottle . a toner bottle is adapted to fit the apparatus for discriminating toner bottle types , and a toner bottle is adapted for the apparatus for stirring toner . the genuineness of the toner bottle product is checked by sensing a rib assumed to be formed with a predetermined length on the outer surface of the toner bottle . toner is stirred by continuously rotating the toner bottle in forward and reverse directions . the toner bottle can be easily rotated in the forward and reverse directions by sensing the rib of the toner bottle by using the sensor . since the load of rotation of the toner bottle changes in accordance with the amount of remaining toner , the rotational speed of the toner bottle is sensed by using the sensor to check whether toner is close to empty .