"Hypnosis is, perhaps, one of the most misunderstood and controversial methods of psychological treatment. The myths and misconceptions that surround hypnotherapy mostly stem from people’s ideas about stage hypnotism. The truth is that stage hypnotism is essentially a theatrical performance and has about as much in common with bona fide clinical hypnosis as many Hollywood movies have with real life.
The fact is, however, that hypnosis is a genuine psychological phenomenon that has valid uses in clinical practice. Simply put, hypnosis is a state of highly focused attention or concentration, often associated with relaxation, and heightened suggestibility. While under hypnosis (i.e., in a hypnotic trance), it seems many people are much more open to helpful suggestions than they usually are.
The positive suggestions that people are given while hypnotized are referred to as “post hypnotic suggestions” because they are intended to take effect after the person emerges from the trance and is no longer under hypnosis."