Its or It's

This one took me forever to get a hold on, all the way through last semester. I had to be really thinking about what I was writing to remember to get it right. Even now I have to proofread to make sure to check it. Just to make sure I finally have it right, I looked it up.
Its-possessive form- Its mine. Its his/her bicycle.
It's-contraction of the words it is.
What messed me up was that usually you use the apostrophe to show possession. This is one of the exceptions.


http://www.wsu.edu/~brians/errors/its.html