[OrangeCat]

A good overview:
http://www.investopedia.com/university/options/

Options on futures:
http://www.orionfutures.com/opts.htm#terms

Options as used for employees:
http://money.howstuffworks.com/question436.htm

If you really want to get into it, here is an online tutorial:
http://www.cboe.com/LearnCenter/Tutorials.aspx#Basics