Howdy,Denny
The term seems to have evolved into loinbacks being marketed as "babybacks" by the restaurant chains and supermarkets.
There are Danish baby backribs that used to be marketed heavily.
There had been a retaurant trend ,especially around Memphis,of buying up all the available backribs that were 20 ounce and under.
They were sold as babybacks.
The easy answer to your question is they are the same beast.
Here is a site that is pretty good with current market terminology,without getting too technical.
RibmanYou need to cook till they suit you.
I'd let them go 3 hours at 225�,meat side down, before I checked them.
The 101s will give the signs to look for i.e. meat pulled back from bone ends,sag to almost breaking if lifted with tongs in the middle,tear one off and eat it,run a toothpick between the bones to check for tender,etc.
This is not the way to cook them,just a way.
Have fun.
