Glad you asked...
Well there are two definitions of NOS. There is a popular energy drink known as NOS, which I think tastes like spit, fear, and shame all in one bottle. The other definition of NOS is Nitrogen Oxide Systems, which are the cartridges you see them turn on in the Fast And Furious movies. You know, where they press the little red button and go 500 miles an hour. It can also stand for Network Operating System, if you are a computer geek type. You can find more information here:
http://en.wikipedia.org/wiki/Nitrous_oxi...