What makes using OBD2 system, so much better than OBD1

RE is controlled by the "main" computer. Also be careful, don't know about all makes and models, I had a GM car was a "half way in between" OBD1 and OBD II half the scanners on the market would not read the damn thing. I think this all happened around 95--ish for GM, don't know about Chrysler
got to love GM, No worrys I'm a mopar guy, no GM stuff here.