Italiano Siciliano Languages?.... HELP!?

k, I am an Italian/American girl. I recently learned that my dad is Sicilian instead of Italian like my mom, so i guess that makes me Italian/Sicilian/American. My dad never comes around so I never knew until I got on ancestry.com. I am learning Italian right now, and I was wondering the differences between Italian & Sicilian. I have come across some Sicilian words that are nothing like the Italian equivalent. So if someone could please explain to me the differences or point me in the direction of a good website that can help me with both of the languages. Or could help me via E-mail I would really appreciate it a lot. thanks! <3