You will see the words a number of times when you read about hypnosis: the subconscious mind, also called the unconscious mind. Through time there has also been several different interpretations of what this "unconscious mind" is. In recent time Richard Bandler of NLP has coined the term with the meaning of "Whatever we aren't conscious of at any given time". It's only a term that's used because it enables us to describe different phenomena about human beings. At this very moment your heart is beating (or else it would be hard for you to read this), you breathe with regular intervals, and you see and interpret this text without actually knowing how you do it. All this functions out of your conscious awareness.

In the unconscious part of our mind, we build our model of the world. A model that is different from anyone elses, a model that has a lot in common with members of our close family, since it is build in terms of the way we are brought up and the experiences we have. These models of the world we carry around will result in beliefs about certain things, it contains a lot of constraints to allow us to function around other human beings, and engage in social activity with them.

Sometimes we carry around some very limiting beliefs, often hypnotically installed by well-intentioned parents or family members. When such beliefs are unconscious they are hard to challenge and can therefore prevent you from achieving the things you want. It may be a teacher who told you that "You will never be able to spell like the others". Believe it or not, such things said to a child by an authorative figure can result in spelling problems through the whole life of the child.

Somehow the hypnotic state of mind allows you to access the unconscious mind and discover previous experiences and reinterpret them with all the knowledge you have aquired since. This is really some of the essence of changework with hypnosis. The conclusion is, that there is no such actual thing as an unconscious mind, but it's a term that enables us to distinguish things that aren't readly available to the consciousness from everything else.