You hear stories about someone's ferret that would always bite and had to be kept in a cage. Just remember, in the year 1997, there were over 320,000 reported dog bites in the United States. A ferret that is raised with love, shown plenty of affection, kept clean and healthy, played with and allowed adequate time out of his cage will return your efforts. You must start young with your ferret in your raising and training. Young ferrets are easier to train than older ones.
Ferrets are very intelligent and learn quickly.
Just because they are small, do not assume you should treat them like hamsters. Young ferrets should be discouraged to nip at human hands. They do not know that if they bite us too hard it hurts. Ferrets have very thick skin and bite the living tar out of each other without much fuss. This is part of their sibling play behavior.