What exercises can be done for those with a bad back??

This question comes up about every other week...With very little responces.  Just thought we could brainstorm on what people can do.  I have a bad back...Doctor's wanted to operate about 20 years ago...I said no.  The weightloss helped big time on the back problem.
So here are my ideas on what can be done for those who wish to exercise but are limited because of their backs.
# 1.  Exercise band...The more I think of these, the more they make sense.  You may want to Google or Youtube exercise bands or elastic band exercises and see what comes up.  Yeah, there will be a lot ads on the Google search, but some good info out there.
# 2.  Swimming or aqua aerobics...Another seach engine may help you.
# 3.  Talk to a physical therapist.  They really are the ones who would know what works and what to avoid.
# 4.  Talk to your local university...If they have a physical ed or kinesiology department...They may give you insight into what will work or where to go for more information.
I have a BA in physical education from a 4 year school (over 30 years ago).  Just after I left they started to add adaptive PE to their curriclum.  So any other thoughts on what exercises would work for those with back problems??
 

I found that when I strengthen my core, it really helped with my back.

Just as you mentioned, swimming and weight loss. As far as medications go, Cymbalta has been found to be really helpful with back pain, in addition to helping with anxiety. My dad has been struggling with back pain for over 20 years. When he was 35, the doctor told him that he had the back of a 65 year old. Cymbalta and weight loss were the first things to actually help with his back pain.