Newbie Needs Help!!

Well the price won't tell you what kind of a bike it is. To tell you what kind it is I would need a picture, but I'll try anyway. Well the main difference between a mountain-bike and a racing bicycle (or road bicycle) is the speed. A road one has a very light frame and thin tires and usually doesn't require too many accessories (probably the heaviest piece would be the gearshift, depending on its quality). The disadvantage although are its instability and dependency on plain surfaces (it's hell to run with it on a country road). On the contrary, a mountain bike is sometimes a monster of a bike, with solid frame (but recommended to be a solid light frame), wide tires and I've managed to fly down a mountain on the bumpiest and worst roads you can find. The bad side it's that it's much harder to pedal on it, requires more stamina and various parts need to be replaced regularly, depending on its use (like break cables and stuff). Overall, you said you wanted to do urban biking, so I would suggest a road bicycle, although you can also use a hybrid, which would be both efficient on the road and off the road (but prices can get really high, depending on your choices). Hope I was of any help, happy biking!