NLP stands for Neuro-Linguistic Programming, a name that encompasses the three most influential components involved in producing human experience: neurology, language and programming. Neuro-Linguistic Programming describes the fundamental dynamics between mind (neuro) and language (linguistic) and how their interplay effects our body and behavior (programming). NLP is used to change limiting behaviors, break bad habits, gain mastery in whatever area is important to you, and build self-esteem. It is excellent for learning how to gain rapport with other people and is often used by attorneys and sales people. NLP will enable you to comfortably gain rapport with anyone in any social situation. It has been used by many people and it is the basis of the work of Tony Robbins.
NLP was originated by John Grinder (whose background was in linguistics) and Richard Bandler (whose background was in mathematics and gestalt therapy) for the purpose of making explicit models of human excellence.