just because you're female doesn't mean you're not a mammal, we have hair virtually everywhere (the exclusion being the palms of our hands and the bottoms of our feet) some of it is just dark and thick while the rest is light and fine.
two options on "getting rid of it":
shave, which you will have to do as often as you shave your legs or sometimes more often.
wax, which will be semi-painful but the result will last longer if done properly.
neither is a permanent fix, but not everyone can afford lazer surgery... of course if you can, there's always that too.
It is a medical fact that a woman produces pheromones from her armpits, and I have found that a woman who DOES NOT comply with the "social norm" of shaving/waxing (or whatever else) their armpits actually produce a higher level of pheromones; to the extent that pre and during sex these pheromones are a HUGE aphrodisiac and as a result increase both partners sexual experience.
However, a woman that does shave/ wax etc. actually "hardens" the skin of the armpit, which in turn reduces the release of these natural pheromones.
I actually have a wealth of information on this topic, with actual experiences and "studies" and anyone who is interested can add me as a friend here and I can then share these with you.
Did you know that you have hair everywhere on your body except the palms of your hands and the soles of your feet? Hair is normal and natural!
As for what you do with it, that's up to you. I'm very picky about shaving because it doesn't feel clean to me when I don't, but if your body hair isn't all that noticeable, then you're probably better off leaving it alone.
the hair on my arm is blonde so you can't really see it-i wouldn't get rid of it because no-one notices it. I know lots of girls that get rid of the hair on their arms because its very noticeable though.