NLP  Neuro Linguistic Programming.

Briefly, very very briefly it is a philosophy of personal improvement. It includes a set of tools and techniques pulled together from the learning of many disciplines. It is used to address issues such as phobias, habit disorders, psychosomatic illnesses and learning disorders. Is strongly supports the potential for self determination through overcoming learned limitations. 

NLP in part is a therapeutic technique to detect and reprogramme unconscious patterns of thought and behaviour in order to alter psychological responses. The basic principle of NLP is that it is in an individual`s power to change their own subconscious programming for the better.

It is used extensively by hypnotherapists and life coaches to make significant changes in beliefs and behaviors sometimes in a few one hour sessions.

To understand the power of NLP you need to experience it.  Reading is useful but it is something best done with a guide.  Trying NLP alone is a little like learning to cut your own hair. You can do it but the results can be unpredictable.