Hypnotherapy is a type of alternative medicine and is not a definitive treatment. It is usually complementary to mainstream treatments of medication and psychological counselling. Hypnotherapy is performed only for people who are willing to undergo such treatment.
Hypnosis is a heightened state of awareness brought about by intense concentration and complete relaxation. While in a hypnotic state, a person is not asleep, but is in an altered state of consciousness that allows them to talk to the therapist without reservations.
All people can be hypnotized, but it is a prerequisite that the person himself wants to be hypnotized.