What is buprenorphine?

I am currently prescribed Buprenorphin. I was at a pain clinic for 5 years,and was prescribed a HEAVY regimen of opiates. I detoxed almost 3 years ago. Four months out of detox I started taking Buprenorphin, as my body STILL didn't feel strong, or well enough to function on a necessary level. Buprenorphin is just the "generic" substitute for Suboxone,(a maintainence medication for opiate dependency)thus being quite a bit cheaper, as suboxone is generally quite pricey!