Hi - I bought a lipo battery, but I don't know if it's a 10c 14c or 20c...I don't even know what this name stands for? what does that mean?

Well Alex, LiPo means Lithium Polymer. That's the materials the pack is made of. Somewhere on the pack it should have some numbers. There should be a voltage rating, ie. 7.4, 11.1, 14.8, etc. There should be a milliamp capacity, such as 1100mah, 1500mah, etc. Then there should be a discharge rate, such as 10C, 20C, etc.
Voltage= how many cells there are, unless some cells are parallel. that's what the 2s, 3s, 3s1p, etc. stands for. 2s= 2cells, 3s=3 cells, 3s1p stands for 3cells in series, 1 parallel. EachLiPo cell is 3.7 volts, so 1s= 3.7v, 2s= 7.4v, 3s= 11.1v,etc. When cells or packs are run parallel, the voltage stays the same. When packs are run in series, thevoltage increases by the number of cells added.With me so far??
Nextis capacity. The milliamprating ishow much capacity the battery can hold.The higher this number is, the more capacity the battery has.
Then there's the discharge rate, 10C, 20C, etc. This is the rate that the pack can safely discharge it's capacity without excessive heat or damage to the pack.
All of this needs to be taken into consideration when deciding what motor you run, prop size, weight of model, type of flying, etc.
Hope this helps.

wow - you summed it up real nice.! the only thing I didn't get was the 10c 20c, etc part....I have a unit that has a <span style="font-size: small;"><span style="font-family: Comic Sans MS;"><font face="Comic Sans MS">Consumption Current of 450mAh

so, what is the battery rating I need for something like this? 10C 20C ? what does the 10C mean?
I am assuming it's discharge rating, but how much exacly for each rating?

my battery is an 11.1v 2200mah 8C
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<span style="font-size: larger;"><span style="font-family: Comic Sans MS;">Alex ... 10C means the battery can safely discharge up to 10 times its capacity. Hence a 1,000 mAh battery of 10C can disharge up to 10A. A 2,500 mAh pack of 20C will discharge up to 50A and not bloat (let's assume the manufacturer is being truthful). Your 2,200 mAh pack of 8C is good for 17.6A only. Is this clear?

If your unit has a current consumption of 450 mAh only then its pulling 0.45A ... are you sure its that little? Double check on that. If that system pulls that little I doubt anyone will want to fly her with a 2,200 mAh pack, assuming its a plane.</span></span>

it's not an airplane it's a video transmitter.
so my battery should be good for it rihgt? since I can discharge at 17amps and I am only consumming .4 amps.

I am confused with one thing. why do you say "<span style="font-size: larger;"><span style="font-family: Comic Sans MS;">If that system pulls that little I doubt anyone will want to fly her with a 2,200 mAh pack, assuming its a plane."

the way i understand it is that I am only pulling  .4amps  and the max I can pull is 17amps which should be more than sufficient. If not, then I am still confused about the meaning of C rating<br type="_moz"/></span></span>

Sorry about that Alex ... I thought it was an airplane and a plane consuming 450 mAh is pretty small. Yes, your battery is more than enough.

Alex, i'll try to explain it differently, see if this helps.
say you have a battery that's 1000ma for example. You can simplify that by saying it's a 1 amp battery. 1000ma=1amp, with me so far? So, knowing that, a 2500ma pack is a 2.5amp pack, and so on, ok? I know that seems a bit confusing, when you think that the motors draw higher amperage numbers than that, but that's where the discharge rate comes in.
For example, a1000ma, or 1 amp pack, at 10C, can deliver 10amps of current safely. Most packs also give you a burst rating. Say that same 1000ma 10C pack has a burst rating of 15C for 15 seconds. That pack can safely deliver a burst of 15 amps for 15 seconds without damage to the pack. With me so far?
So what that means, say you have a plane with a motor and prop setup that will draw 10 amps at full throttle, and you need a battery pack that will safely run that setup without excess weight-remember, the larger the pack, the more it weighs-. If you decided to run that 1000ma 10C pack, it would be ok for that plane. You wouldn't want to run a 5000ma pack on that plane, because it wouldn't even leave the ground with that much weight. Understand? The opposite is true also, you wouldn't want to try to run a 500ma pack, you wouldfry the battery by discharging it too quickly by exceeding it's discharge rate.
So, knowing that info, your requirement of .4 amps is well within the capacity of the battery you want to run, the battery is way overkill actually. Be sure that the voltage rating for your battery isn't too high for the camera transmitteryou're going to run, or you'll probably fry it. You could run a much smaller pack and still be ok.
If you had a 2500ma 3s 20C pack, that pack would be capable of delivering 50amps at 11.1 volt continuous. 3s @ 3.7v/s= 11.1v. -2500ma, or 2.5a x 20C = 50 amps.
You get it now? That is, of course, if the battery manufacturer is honest with their advertised capacity and rates. It's best to go a little higher capacity than you need, just so you're not pushing all of your equipment to the max all the time. It's the same as when you get an ESC, you always want some reserve capacity, but not too much to where you add unwanted weight.

awesome! ok I got it.
I always like to overkill everything that I do - it makes me feel safe and it allows me to push the envelop, which is why I like this hobby so much. If I never pushed the envelop, I would have never crashed an airplane :-)
thanks guys for all your help.

I think that weight is not going to be an issue with the airplane that I am flying this system in because of the wing span and lift to weight ratio.