Classes in USA:
Twelve-To-Eighteen Months - For dogs twelve to eighteen months of age, that are not yet champions
Novice - For dogs six months of age and over, which have not, prior to the date of closing of entries, won three first prizes in the Novice Class, a first prize in Bred-by-Exhibitor, American-bred, or Open Classes, nor one or more points toward their championship
Bred By Exhibitor - For dogs that are exhibited by their owner and breeder, that are not yet champions
American-Bred - For dogs born in the United States from a mating which took place in the United States, that are not yet champions (mandatory class).
Open - For any dog of the breed, at least 6 months of age (mandatory class).
All the dogs that won first place in a class compete again to see who is the best of the winning dogs.
Males and females are judged separately.
The Winners Dog and Winners Bitch compete with the champions for the Best of Breed award.
For more information go to: http://www.akc.org/