controlling somebody unknowingly is hypnotism
Disagree! Hypnotism is not about controlling people; quite the opposite, in fact.
Hypnosis is a naturally occurring state of mind in which people are highly focused on (absorbed in) specific stimuli to the exclusion of all else: eg when totally immersed in a book or film; fascinated by your lover, or performing some everyday task automatically whilst thinking about something else. Most people enter such mental states regularly during the course of everyday life; it's normal.
Many psychologists believe most people enter "right brain states" (ie when the right brain function - responsible for emotion, intuition, fantasy etc - predominates over the left - responsible for logic, critical analysis etc ) for brief periods approximately every 90 minutes. Typically this will be described as "daydreaming", & seems to be a normal part of the brain's daily functioning - it's resting, "filing data" or whatever. During such phases people are in trance states.
Hypnotism is simply the deliberate utilization of this normal human capacity to enter trances for some specific purpose - entertainment, relaxation, therapy etc.. It has been observed that people in hypnosis typically manifest similar characteristics to people in the REM phase of sleep (when dreaming occurs): their eyelids flicker, & often the eyes roll up into the head. They may experience limb paralysis, and often experience time distortion, and possibly hallucinations if suggested by the hypnotist. It's not uncommon for deeply hypnotised people to experience spontaneous sexual arousal/ erections (penile & clitoral) - again, typical of the REM sleep phase. Some, therefore, theorize that hypnotism is, in fact, artificial induction of the REM state in an otherwise conscious person.
A person in hypnosis is not asleep; they're in a deeply relaxed but hyperattentive state during which they're totally absorbed in what the hypnotist is saying to them. In order to achieve this state the person must cooperate with the hypnotist/ be willing to be hypnotised.
Although apparently totally compliant, in fact, hypnotised people will not do anything contrary to their beliefs/ values. Most hypnotised people remain fully aware at all times; some particularly adept people do enter a somnambulistic state, & can remain deeply hypnotised with their eyes open, walk around, experience vivid hallucinations etc.. Such people often have total amnesia about events during their trances, but this does not mean they were "under the hypnotist's control": they still would not do anything offensive to their basic beliefs/ values, & if such were to be suggested would simply fail to comply or come out of trance immediately. The capability to enter such a deep trance simply indicates a very high ability to concentrate intensely combined with a readiness to "let go", become totally absorbed in the experience, and trust the hypnotist. This could not happen to an unwilling/ suspicious person, let alone one who was unaware of what was happening!
It's a total myth that hypnotism is about controlling people against their will or without their knowledge: hypnotism is about cooperation between hypnotist & subject - in effect, the hypnotist simply guides the person into a trance state: s/he is a facilitator enabling the person wishing to be hypnotised to utilize fully their natural human capacity for entering trance states.