What is NLP?

NLP, or neuro-linguistic programming, is a school of psychological techniques that effectively communicates with the listener's subconscious or unconscious mind. In modern-day terms, brain-hax. The end result is that you can communicate/argue/negotiate/threaten/persuade people (or yourself) much more effectively. Astoundingly, significantly, suspiciously more effectively!

• Neuro: Pertaining the neurons, or nerves, the brain's communication tool
• Linguistic: Pertaining to language
• Programming: To configure or set the way something works 

What can NLP do?

The tagline of NLP-secrets.com is "upgrade your mind" which is the best way I can describe the effects of NLP. You can upgrade your mindset, intelligence, memory, senses, appearance, and your communication skills. You can gain the ability to improve, enhance or modify ANY aspect of yourself or someone else.
NLP can be an extremely powerful tool, when used correctly. I have seen Derren Brown, a world-famous mentalist, use NLP techniques to talk a total stranger into giving him their wallet - in 20 seconds flat! NLP can be used on yourself as well as other people, with hundreds of opportunities to do so occuring every day.

A basic example of NLP

The most basic example to illustrate this, is if I said to you:
"Don't think of a blue duck!"
What's the first picture that came to your head? A blue duck. The command "think of a blue duck" lay within that short sentence. Of course, before you have a chance to not think of a blue duck, your unconscious brain has already put a picture of a blue duck up and stuck a DON'T label on it saying "this is the thing to not think about."
Very basic, yes? Everyone knows that. How could that possibly be used to help me communicate?
Okay, how about we use that same lesson, and apply it to another example, slighly more useful. Imagine you've got a 5-year-old son, and he starts trotting towards a busy road. We've established that if we yell to him "Don't walk on the road!" - there is every chance he might take a split second longer than usual to process the full command.
Instead, you'd say to him "Come here right now!" which might make a massive difference if a speeding car is just seconds away. This is a very basic example of NLP, in fact it is barely classified as NLP, as it just scrapes the surface. Another example of this technique might be when people say to themselves "Okay, don't forget to buy milk on the way home." They are more likely to forget. Instead, they should say "Remember to buy milk when I'm passing the shop." That way, they picture the shop as they say the word, and when they see that picture in real life, ie, they are likely to remember to buy some milk. (If they wanted to be even more sure to remember the milk, they should say "When I pass the shop, I'll have to be careful because milk will explode out the windows, covering me in cold milk." to invoke senses and emotions into the mnemonic - but that's another subject!)
On a level of 1 to 9, this technique is a 1 in terms of complexity and depth. There are hundreds of tiny tricks we can use in neuro-linguistic programming, as you get higher in the scale you are getting closer to hypnosis.