1. What does NLP stand for?

What Does Neuro-Linguistic Programming" ("NLP") Mean?

Okay, let me start by saying that there are at least three widely recognized "meanings" for NLP (and several more which are less well-known). The widely-known meanings are:

In connection with Transcendental Meditation, NLP refers to the "Natural Law Party".

In the world of computers, and AI (artificial intelligence), etc., NLP stands for "Natural Language Parsing/Processing".

In the area of psychology - and on this website - NLP, or Neuro-Linguistic Programming, is a specific modelling technique. NLP is not the same thing as the field of NLP (FoNLP) which covers NLP itself, plus the related concepts and techniques, plus training in any element(s) of the FoNLP (including training for trainers of the FoNLP).

Neuro
This refers to the fact that the areas covered by the FoNLP (field of NLP) - language, perception, communication, behaviour, etc. - all stem from neurological activity. That is, activity in the brain. It is important to note, however, that the creators of NLP and the FoNLP were/are not concerned to offer a scientific explanation of this idea. On the contrary, at the training course which was the basis for one of their books they stated very unambiguously:

As modelers, we're not interested in whether what we offer you is true or not, whether its accurate or whether it can be neurologically proven to be accurate, an actual representation of the world. We're only interested in what works.
(Frogs into Princes, Bandler & Grinder (1979). Page 18 (UK edition). Italics as in the original.)

Linguistic
Refers to words - and how we are affected by the words we hear and use.

There are numerous studies of the way our perceptions are influenced by the words, such as the "Reconstruction of automobile destruction" experiments (1974) conducted by Elizabeth Loftus and J.C. Palmer.
In the initial experiment subjects were divided into five groups and all shown the same series of seven short video clips in which two cars were seen coming into contact. After each clip the subjects were asked to fill in a questionnaire about the clip.

The point of the experiment lay in one specific question in each questionnaire:

"About how fast were the cars going when they ???? each other?"

The questionnaires for all five groups were exactly the same EXCEPT for the word(s) indicated by "????". Yet when the results were averaged out by group, the estimated speeds seemed to provide a clear indication that the subjects' perceptions had been affected by the wording of that key question. In fact the estimates varied by up to 9 miles per hours, thus:

Where the question asked: "About how fast were the cars going when they contacted each other?", the mean estimate was 31.8 mph
Where the question asked: "About how fast were the cars going when they hit each other?", the mean estimate was 34.0 mph
Where the question asked: "About how fast were the cars going when they bumped into each other?", the mean estimate was 38.1 mph
Where the question asked: "About how fast were the cars going when they collided with each other?", the mean estimate was 39.3 mph
Where the question asked: "About how fast were the cars going when they smashed into each other?", the mean estimate was 40.8 mph

(Italics have been added here, for emphasis.)

Programming
Taken from the computing term, this basically means that as we go through life we collect all kinds of "programs" (somewhat similar to what are referred to in Transactional Analysis as "scripts.")
The key idea is that just as a computer will try to execute all of the instructions in a program it is "running", regardless of whether they make sense, so human beings tend to act in accordance with the ways in which their experiences have "programmed" them, even when the program doesn't make sense (like people speaking very slowly and loudly to foreigners as though that will somehow improve the quality of their communication).
On the positive side, just as computer programs can be debugged, or even completely re-written, so we can examine the mental programs we live by and, if we don't like the results they generate, we can "re-write" them to get results we do want. Or we can adopt completely new programs that have been shown to be effective for someone else. In other words, NLP is about our ability to change our lives in the way we want by changing our thinking and our behaviour.

Important Note:

According to Korzybski, who first coined the label (see below), there should always be a hyphen in "neuro-linguistic" to indicate that this refers to two individual entities - neurology and linguistics - working together, as compared with "neuro linguistic" (two separate entities) or "neurolinguistic" (a single entity), neither of which make this distinction clear.
In Korzybski's work, neuro-linguistics bears a resemblance to the Sapir-Whorf Hypothesis, which suggests that our perceptions are significantly influenced by our use of language. In the FoNLP, however, the meaning extends into the area of study now known as Cognitive Linguistics, which includes the view that the way we perceive the world significantly affects our use of language.
That is to say, the Sapir-Whorf Linguistic Relativity Hypothesis, to give it its full title, and Cognitive Linguistics seem to offer an "either/or" choice - either 'the language we have available to us affects our perceptions' or 'our perception affects our use of language'. The FoLNP, on the other hand, embodies both propositions.

By the way, the hyphen in "neuro-linguistics" is also important because "neurolinguistics" is a field of study in its own right. In this regard it is worth noting that Alfred Korzybski coined the term "neuro-linguistic" at least as far back as 1936, long before it was adopted by Richard Bandler when he coined the term "neuro-linguistic programming" in the mid-1970s.
Despite complaints from people such as psycholinguist Professor Willem Levelt, (now Director Emeritus of the Max Planck Institut in Nijmegan, Holland), the name "neuro-linguistic programming" is clearly not the same as "neurolinguistics", a term attributed to Harry Whitaker, who founded the Journal of Neurolinguistics in 1985. And the Field of Neuro-Linguistic Programming (FoNLP) does not impinge on the area of neurolinguistics, which is the physiologically-based study of how damage to the brain can affect out ability to use and understand language.
(Scientific studies of the relationship between the brain and linguistics were going on for many decades before 1985, or course, but for a very long time it was known as aphaseology.)

Recommended reading: Introducing NLP and NLP Workbook