Sorry ... but another 50mm question.

[[ If I understand it right, the D-80 apperture effect is only f2]]

You do not understand this correctly. The camera body has nothing to do with the maximum aperture of the lens. If the lens is a f/1.4 lens then the largest available aperture is f/1.4 regardless of camera body.

[[You don't have to explain (unless you would like to), but I'm simply trying to find a place that can explain what all of this means so I can properly assess and purchase a lens that will work best for me.]]

How exactly will anyone be able to tell you what the acronyms mean if they can't explain what the acronyms mean? I don't understand what you're asking for here. Your goal should be to learn what these terms mean and how to apply them to your own photographic needs.

If I understand it right, the D-80 apperture effect is only f2, so there is no difference in puchasing a f1.4 or f/1.8.

That is not correct at all! The D80 will give you whatever apperture the lens has. This is not something that is ever determined by the camera body.
AF-S simply means that the lens is fitted with a silent internal focusing motor, as does HSM. the f/1.4 D means that the lens gives the camera information about the distance 'D' to the subject.
FWIW, all those lenses will work perfectly on a D80 and a D50.

"How exactly will anyone be able to tell you what the acronyms mean if they can't explain what the acronyms mean?"

All he was saying was "you don't need to type it all out (unless you want to), a link will be fine."

http://www.sigma-imaging-uk.com/support/faq_lens.htm

http://www.ndreview.com/nikon-glossary/nikon-lens-term-glossary/

AF-S means the lens has ultrasonic motor in the lens itself (in case of D40 which doesn't have a motor, AF-S are the only lenses that autofocus with D40)
AF-D came after AF, and the "D" stands for Distance which is communicated during flash.. something something
EX DG HSM... those are good letters, the more 2-3 letter acronyms with non-Nikon lenses the better :-). I think HSM=hyper sonic motor, and EX is something, not "excellent" but it should make the lens excellent
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you want to stay with Nikon if you can, otherwise there are all kinds of issues..... unless you want to save 30% or more of the price and you're ok with possible issues in future, including autofocus, lens not registering properly in EXIF, front-focusing issues, etc
there is 50mm f/1.4D and 50mm f/1.8, and latest is 50mm f/1.4 AF-S. $200 vs $110 vs $300... and i would pick the $110 50mm f/1.8D case closed, easy.... and you can spend money on something else [photographic]
the f/1.4 or f/1.8 is the maximum aperture of the lens, has nothing to do which body you are using. as you can see, it's $100 difference from f/1.4 vs f/1.8 in this case. the f/1.4 lens specifically is more appreciated for portraits, while the f/1.8 lens is more appreciated as all around, good enough, just as good as f/1.4 lens in many cases

Laura, Robert is being facetious with most of his post, and that may or may not be obvious to you depending on your experience level.

Nikkor AF-S 50 mm f/1.4 - What does AF-S mean? Nikkor 50mm f/1.4 D AF - What does D AF mean.Sigma 50mm f/1.4 EX DG HSM - What does EX DG HSM mean? (Digital and HSM is how Sigma says auto focus

http://www.nikonians.org/html/resources/nikon_articles/other/compatibility.html

Also every lens is different, for example Nikon 85mm f/1.4 is $1100 but 50mm f/1.4 is $200... or 85mm f/1.8 is $400 but 50mm f/1.8 is $110

The best would be to get for example 50mm f/1.8 and take so many pictures that you start seeing limitations of the lens, then rent a more expensive version of the lens, in this case $200 is not that much, but other cases are different... and IF you can see a difference in YOUR pictures, then you could benefit from that. Besides the cost, the weight becomes a factor too, the bigger the aperture [or smaller the f-stop number.... so f/2.8 is going to be lighter lens than f/1.4].

If you just have a 18-55mm kit lens with f/5.6 on the high end,
* $110 50mm f/1.8 would let you do portraits and enjoy f/1.8 or so at 50mm, being close-up to the subjects
* $770 105mm f/2.8 VR macro would let you do macros and portraits too
* $1100 300mm f/4 AF-S would let you take pictures of animals, birds [some birds... it's all about the technique and patience and waiting if you want awesome keepers.. and tripod too]

Those 3 lenses above you can do amazing things with, and it's a lot of money, but it's still the cheap HIGH-QUALITY way to get awesome pictures. The zooms like 70-300mm f/4-5.6 and 55-200mm f/4-5.6..... well sooner or later you will realize their limitation and get frustrated with, and one day you try the higher priced fixed primes like 105mm and 300mm f/4 and then you'll appreciate them..... assuming your technique has progressed to see pictures in your head before taking them :-)

And don't be afraid to ask questions, that's how you learn

Wow, Rob? Who ate your cupcake? I apologize if my wording was not to your liking, but it's obvious that I don't know what I'm talking about. Hence my posting to this forum and the request for help from experts like you. Thanks for more accurately restating my need: "Your goal should be to learn what these terms mean and how to apply them to your own photographic needs." Exactly. Which is the reason for my posting.
Sp, thanks for seeing through all the drivel and giving me what I needed.
Hammas and Robert, thanks for the explanations. I was given this erroneous information from a salesman in a camera shop and am glad that I double-checked with you.
Should anyone else feel the need to expound or pummel, have at it. I'll be in the bathroom crying.

I think it should be a rule that anyone who buys a Nikon DSLR and a kit lens also buy the 50mm f/1.8 (AF-D). Doing so will teach an incredible amount about:
Prime vs. zoom technique.
Fast vs. slow DoF and how it affects composition.
Prime vs zoom/kit sharpness.
Full aperture AF speed on your camera.
Etc., etc.

Given that the other basic tools which can drastically improve a beginner's photography cost several times the cost of this lens, it really ought to be a requirement. (I'm thinking dedicated flash and decent tripod and head.) The really nice thing about the 50mm f/1.8 is that it is priced to be damn near disposable. Hell, you can probably pick one up used for the cost of a high quality UV filter. As it stands it cost less than a high quality circular polarizer.