I am an American who would like to understand Islam. Could anyone teach me the basics of it?

Hoo boy. I can see myself coming under rapid fire for even touching this subject. But I don't care. I want to know this thing that so many people jeer and hiss at. I already respect everyone for their religion, whether or not I really understand it, but in this case I think I ought to know what it's truly about before I go saying anything about it like some ignorant jerkface. So please educate me...