What information does the sim card hold?

After my iPhone fell in the water and stopped working, I have decided to get a new phone. It is before my upgrade is due, so I will have to pay a penalty for having it early. However my dad suggested handing my phone into them to maybe reduce the price.
Anyway, if I take my sim card out, what will remain on my phone itself. Because I do not want the people seeing like my pictures, or any other personal details.

So what will remain on my phone, and what will go?

It will be all your apps pictures text msgs contacts music games

Sim card hold contacts, so pretty much everything will remain on your phone besides your contacs and your MEID which is your phone number.