How to know if a crib is a drop side?

Olivia
My mother kept my crib from my baby days. It's a metal crib and it doesn't seem to be a drop side. When you try to lower one side it's very hard and doesn't come down partially like I've seen in pictures of drop sides. I don't think I've ever seen a drop side crib in person before so I'm not sure what I'm looking for.. How do I know for sure its not a drop side? And yes I know when baby comes to remove the toys and whatnot. 
Update- Thanks for the answers ladies! I'll look into it some more. My nephew used to sleep in this crib also, and I didn't know it was a drop side.. I don't plan on using the crib for a good bit. I'd much rather have baby in my room. But thanks for the advice. And when the time comes I'll invest in a new one.