Therefore, Braid defined hypnotism as a state of mental concentration that often leads to a form of progressive relaxation, termed "nervous sleep". Later, in his The Physiology of Fascination (1855), Braid conceded that his original terminology was misleading, and argued that the term "hypnotism" or "nervous sleep" should be reserved for the minority (10%) of subjects who exhibit amnesia, substituting the term "monoideism", meaning concentration upon a single idea, as a description for the more alert state experienced by the others.[23]
Mesmer developed a general theory of disease he called “animal magnetism,” which held that every living thing carries within it an internal magnetic force, in liquid form. Illness arises when this fluid becomes blocked, and can be cured if it can be coaxed to flow again, or so Mesmer’s thinking went. To get that fluid flowing, as science journalist Jo Marchant describes in her recent book, Cure, Mesmer “simply waved his hands to direct it through his patients’ bodies” — the origin of those melodramatic hand motions that stage hypnotists use today.”
Cancer patients use relaxation and hypnosis. Evidence from randomized trials shows hypnosis and relaxation are effective for cancer-related anxiety, pain, nausea, and vomiting, particularly in children. Some practitioners also claim that relaxation techniques, particularly the use of imagery, can prolong life, although currently available evidence is insufficient to support this claim.
During hypnosis, a person is said to have heightened focus and concentration. The person can concentrate intensely on a specific thought or memory, while blocking out sources of distraction.[7] Hypnotised subjects are said to show an increased response to suggestions.[8] Hypnosis is usually induced by a procedure known as a hypnotic induction involving a series of preliminary instructions and suggestion. The use of hypnotism for therapeutic purposes is referred to as "hypnotherapy", while its use as a form of entertainment for an audience is known as "stage hypnosis". Stage hypnosis is often performed by mentalists practicing the art form of mentalism.
I paid in the region of 2,000 pounds for hypnotherapy with a fully trained and registered professional hypnotherapist. The hypnotherapy made my problems worse. I find it incredibly frustrating that when I have typed letters to the hypnotherapy organisation that this hypnotherapist belongs to, a lot of what I am actually saying in the letters when explaining exactly why the hypnotherapist's treatment has made me worse, and how my problem works gets ignored. I can see that the Hypnotherapist has not interpreted my problems correctly enough. I do not believe that it is totally fair that this Hypnotherapist's work seems to be above being checked for flaws. I am suffering as a result.

The following person had completed years of graduate school plus substantial hypnotherapy training at various schools before he took our 200-hour program in 2013. He was so impressed that he returned in 2015 and took our training again. Here's his response after completing that. Since he wrote this, he completed our graduate clinical courses twice plus our hypnotherapy training a 3rd time, and is planning to take our training for a 4th time in 2019!

It is used for a wide variety of applications, and studies into its efficacy are often of poor quality[2] which makes it difficult to determine efficacy. Several recent meta-analyses and systematic reviews of the literature on various conditions have concluded that the efficacy of hypnotherapy is "not verified",[3] that there is no evidence[4][5] or insufficient evidence[6][7] for efficacy.