What is the difference between pull ups and chin ups? I always thought they were the same.

I always thought both meant the same but Wikipedia has something different to say.
http://en.wikipedia.org/wiki/Chin-up
.. chin-ups have a grip from under the bar while pull-ups have grip over the bar.

So chin up, your palms face toward you, and a pullup, your palms face away?

pull ups are harder to do and its more of a military style of doing that while chin ups like you said have the palms facing you

i don't know about pull ups being harder, they're different. i can do almost as many pull ups as chin ups and i'm sure that if i did pull ups exclusively i would be able to do more of them.

but the above are correct, pull ups are with your palms facing away and chins are with palms towards you.

Chin ups focus more on the bicep, pull ups put more strain on the lats. Some people find chin ups easier because their lats arent as strong.