In this special mental state, people feel uninhibited and relaxed. Presumably, this is because they tune out the worries and doubts that normally keep their actions in check. You might experience the same feeling while watching a movie: As you get engrossed in the plot, worries about your job, family, etc. fade away, until all you're thinking about is what's up on the screen.
Hypnotherapy is a therapy that spans hundreds of years and has many practitioners across the United States. Researchers have studied whether hypnosis can treat a variety of medical conditions, from irritable bowel syndrome to anxiety and depression. The goal for hypnotherapy is to help a patient learn to better control their state of awareness. In the case of depression, hypnotherapy sessions may be focused on helping a person achieve a state of relaxation. In this relaxed state, they can discuss their feelings and emotions without raising stress and anxiety levels.
Depending on the purpose of the hypnotherapy (i.e., smoking cessation, weight loss, improvement in public speaking, or addressing some deep emotional turmoil), follow-up may be advisable. When trying to eradicate unwanted habits, it is good practice to revisit the therapist, based upon a date prearranged between the therapist and the patient, to report progress and, if necessary, to obtain secondary hypnotherapy to reinforce progress made.

“With hypnosis, you might help someone stop smoking by suggesting the taste or smell of cigarettes is worse than it actually is. But a hypnotherapist can also use age regression to examine the impulse that fuels the client’s habit and discover old conclusions and behaviors. The healing will take place when the client creates new conclusions about old memories and chooses new behaviors rather than smoking.”
Stage hypnosis is a form of entertainment, traditionally employed in a club or theatre before an audience. Due to stage hypnotists' showmanship, many people believe that hypnosis is a form of mind control. Stage hypnotists typically attempt to hypnotise the entire audience and then select individuals who are "under" to come up on stage and perform embarrassing acts, while the audience watches. However, the effects of stage hypnosis are probably due to a combination of psychological factors, participant selection, suggestibility, physical manipulation, stagecraft, and trickery.[152] The desire to be the centre of attention, having an excuse to violate their own fear suppressors, and the pressure to please are thought to convince subjects to "play along".[153] Books by stage hypnotists sometimes explicitly describe the use of deception in their acts; for example, Ormond McGill's New Encyclopedia of Stage Hypnosis describes an entire "fake hypnosis" act that depends upon the use of private whispers throughout.
Braid later acknowledged that the hypnotic induction technique was not necessary in every case, and subsequent researchers have generally found that on average it contributes less than previously expected to the effect of hypnotic suggestions.[35] Variations and alternatives to the original hypnotic induction techniques were subsequently developed. However, this method is still considered authoritative.[citation needed] In 1941, Robert White wrote: "It can be safely stated that nine out of ten hypnotic techniques call for reclining posture, muscular relaxation, and optical fixation followed by eye closure."[36]
Hypnotism has also been used in forensics, sports, education, physical therapy, and rehabilitation.[78] Hypnotism has also been employed by artists for creative purposes, most notably the surrealist circle of André Breton who employed hypnosis, automatic writing, and sketches for creative purposes. Hypnotic methods have been used to re-experience drug states[79] and mystical experiences.[80][81] Self-hypnosis is popularly used to quit smoking, alleviate stress and anxiety, promote weight loss, and induce sleep hypnosis. Stage hypnosis can persuade people to perform unusual public feats.[82]
Systems theory, in this context, may be regarded as an extension of Braid's original conceptualization of hypnosis as involving "the brain and nervous system generally".[74](p31) Systems theory considers the nervous system's organization into interacting subsystems. Hypnotic phenomena thus involve not only increased or decreased activity of particular subsystems, but also their interaction. A central phenomenon in this regard is that of feedback loops, which suggest a mechanism for creating hypnotic phenomena.[183]

Barber et al. noted that similar factors appeared to mediate the response both to hypnotism and to cognitive behavioural therapy, in particular systematic desensitization.[35] Hence, research and clinical practice inspired by their interpretation has led to growing interest in the relationship between hypnotherapy and cognitive behavioural therapy.[70]:105[113]

When you hear the word hypnosis, you may picture the mysterious hypnotist figure popularized in movies, comic books and television. This ominous, goateed man waves a pocket watch back and forth, guiding his subject into a semi-sleep, zombie-like state. Once hypnotized, the subject is compelled to obey, no matter how strange or immoral the request. Muttering "Yes, master," the subject does the hypnotist's evil bidding.

Scenario; you are at a party. Everyone is snacking on food and sipping drinks. You lean against a wall, arms folded, and inhale as you look at the crowd. You scan the room where people are talking while music is playing in the background. You are looking for just the right person that you feel will be the most suggestible. Once you have your prey, it's time to go to work, and this is how you do it.
This finding—that PHA temporarily disrupted some people’s ability to recall the past—echoes decades of hypnosis research. What is entirely new in Mendelsohn et al.’s study is their demonstration that PHA was associated with a specific pattern of brain activation. Consistent with what normally occurs in remembering, when people in the non-PHA group performed the recognition task and successfully remembered what happened in the movie, fMRI showed high levels of activity in areas responsible for visualizing scenes (the occipital lobes) and for analyzing verbally presented scenarios (the left temporal lobe). In stark contrast, when people in the PHA group performed the recognition task and failed to remember the content of the movie, fMRI showed little or no activity in these areas. Also, fMRI showed enhanced activity in another area (the prefrontal cortex) responsible for regulating activity in other brain areas.
Preliminary research has expressed brief hypnosis interventions as possibly being a useful tool for managing painful HIV-DSP because of its history of usefulness in pain management, its long-term effectiveness of brief interventions, the ability to teach self-hypnosis to patients, the cost-effectiveness of the intervention, and the advantage of using such an intervention as opposed to the use of pharmaceutical drugs.[91]

It appears to me, that the general conclusions established by Mesmer's practice, with respect to the physical effects of the principle of imagination (more particularly in cases where they co-operated together), are incomparably more curious than if he had actually demonstrated the existence of his boasted science [of "animal magnetism"]: nor can I see any good reason why a physician, who admits the efficacy of the moral [i.e., psychological] agents employed by Mesmer, should, in the exercise of his profession, scruple to copy whatever processes are necessary for subjecting them to his command, any more than that he should hesitate about employing a new physical agent, such as electricity or galvanism.[54]
In the brain, this state looks stranger still. A landmark study in the prestigious journal Science in the late 1990s, led by Pierre Rainville of the University of Montreal, described a study in which hypnotized people briefly placed their left hand in either painfully hot water, heated to 116 degrees Fahrenheit, or room-temperature water. Some of them had been told that they would be experiencing pain, but that they wouldn’t be very bothered by it — if, on a scale of one to ten, the hurt would normally register at an eight, they’d feel it as if it were a four. As all the participants placed their hands in the 116-degree water, their brains were scanned. The results were clear: Those who had been told that the pain would be less intense showed less activity in their brains — specifically, in the anterior cingulate cortex, which is associated with pain processing.
The hypnotized individual appears to heed only the communications of the hypnotist and typically responds in an uncritical, automatic fashion while ignoring all aspects of the environment other than those pointed out by the hypnotist. In a hypnotic state an individual tends to see, feel, smell, and otherwise perceive in accordance with the hypnotist's suggestions, even though these suggestions may be in apparent contradiction to the actual stimuli present in the environment. The effects of hypnosis are not limited to sensory change; even the subject's memory and awareness of self may be altered by suggestion, and the effects of the suggestions may be extended (posthypnotically) into the subject's subsequent waking activity.[12]

“I never expected how much transformation is possible with this work. This hypnotherapy training went far beyond my expectations. The incredible amount of wonderfully presented material and deep wisdom touched my heart on a very deep level. The combination of hypnosis and very profound and effective methods of processing is incredible. To see the profound changes in my classmates and myself is such a gift, I feel deep gratitude for that. To imagine how much positive change will occur in other people due to this work moves my heart.”

We know it is hard to sort out all the different claims made by some so-called “hypnosis schools and boards.” Stay away from “distance learning” or correspondence courses that claim to certify you as a clinical hypnotherapist. Hypnosis and hypnotherapy is a healing art based on scientific methods. Only basic hypnotherapy theory can be obtained from the right books or videos. Effectiveness is unlikely without live demonstrations, in-depth and advanced discussion, question and answer opportunities and supervised clinical practice.  Just as correspondence courses are inappropriate for counselors, medical doctors and massage therapists, they are wrong for people who want to be effective and successful clinical hypnotherapists.

In the 1950s, Milton H. Erickson developed a radically different approach to hypnotism, which has subsequently become known as "Ericksonian hypnotherapy" or "Neo-Ericksonian hypnotherapy." Erickson made use of an informal conversational approach with many clients and complex language patterns, and therapeutic strategies. This divergence from tradition led some of his colleagues, including Andre Weitzenhoffer, to dispute whether Erickson was right to label his approach "hypnosis" at all.[10]