3.1.2 Classes

Classes can be though of like a template because classes allow you to put objects or things into catogories.
for example :

 Classes : Super, Sports and S-class
Vehicles = Bugatti, Nissan GTR , Lotus LFA

Buggati and Nissan GTR = Super

Lotus LFA = S-class

You can think of classes like animal groups too.
E.G :

Classes : Primates and Carnivora
Animals : Gibbon,Bobcat,Chimp and Brown Bear.

Gibbons and Chimps = Primates
Bobcat and Brown Bear = Carnivora

Sources = http://en.wikipedia.org/wiki/Class_(computer_programming)