Hypnosis is when a person is highly concentrating on something, which puts them in a trance-like state. There are many times in your life that you're in a light trance (hypnosis)--some people call these light trances "autopilot" ie
1. When you're driving to a place you're used to and you don't quite remember how you got there
2. You're fully engrossed in a movie and/or book and lost some time
3. While watching a movie you fall asleep
4. You're fully engrossed in a movie and/or book and someone is trying to talk to you and you don't hear them
Another thing to remember in hypnosis is that we all make ourselves hypnotized--meaning if you don't want to be hypnotized you won't be and conversely if you do want to you will be---Hypnotism isn't something you have done to you, it's something you fully participate in willingly
There are a number of things that can stop you from being hypnotized--
1. You don't trust the hypnotist
2. You have values (religious and otherwise) that are against hypnotism---you're unconscious mind is in charge of your values, which means in this case it won't allow you to be hypnotized.....