Most of you might be aware that, in those days, the mouse used to come with a ball inside, and there were two rollers that actually guide the computer where the ball is moving, and, accordingly, where the mouse is moving.
Daugelis jūsų turbūt žinote, kad tais laikais pelė būdavo su rutuliuku viduje, ir viduje būdavo du voleliai, kurie nurodydavo kompiuteriui, kur juda rutuliukas, ir, atitinkamai, kur juda pelė.