The Accessory belt?

[N9QGS]

Im revising my post cause I think I educated myself a little. Okay there are Timing belts and chains, I guess they are internal to the engine, and the belt on the outside is the Serpentine belt that drives many additional components. I guess what I am specifically asking today since the Yaris has a Timing Chain that is not part of my 100K service, but I do question how do I properly go about servicing or inspecting the Serpentine belt, I guess is there a way to turn the belt so you can easily inspect the whole belt, how long do one suggest going with this belt and how easy is it to change, is it just loosing a bolt to let tension off, and slip the belt off and the new one on, and then reapply tention and tighten bolt?

I am at 80K now, I plan to keep my car at least 200K, if I feel comfortable with it, so I am willing to change this belt at 100K regardless of condition and if the job is easy enough to do in a half hour with minimal tools, any special tools required?

Ron