If you want to grok git, this piece by Nick Farina is very nice:

And because of Git’s explosive popularity, it’s a total Emperor-Has-No-Clothes situation. If you’re anything like me, you probably wondered why you were the only stupid person on the planet who didn’t intuitively get Git already. Even the beloved Github, though unaffiliated with Git, is much the same: as overwhelming as it is awesome.

Go read them at his blog. His great writing style make this post the most readable explanation of git I’ve read so far.