Different units?

I am currently ina BSN program. Ove the summer, I have been accepted into a program at a local hospital in OK. The program helps gets nursing students used to the hospital setting. As part of the program, students get to pick an area work in. This obviously helps the students as well as the hospital. I want to know the difference between the following units.

There are openings in med/surg, general medical, and general surgery. If a hospital has a med/surg unit, plus a seperate medical unit, and a seperate surgery unit, what is the difference between the three? What would a nurse tech do differently on the three? Please be as specific as possible.

Also would you have any idea what MOB-ASC stand for. There is a job open on the unit. There is also a job on the OPAD unit. What the heck is this?

All these questions probably sound goofy. I just want to know what I am getting into before I request a specific unit.

Thanks a lot,

Joy