There has been a question about a pork butt. "What is it?" Well, its not what you think. A pork butt, sometimes called a Boston butt is actually from the shoulder of a pig. A pork shoulder is usually divided into two portions. The upper portion is called the butt and the lower portion is called a picnic.
The butt is slightly harder to cook properly. It contains five different muscle groups that cook differently. The K.C.B.S. rules state that pork butt shall not be parted while cooking. Or something to that effect. This means that for competition cooking you can't cut the butt into different pieces to cook each muscle properly.
I don't know why they have these names, especially calling it a Boston butt. BUT the butt of a pig is called a ham. So when you are eating ham you are eating the butt and when you eat the butt you are eating the shoulder.
Thankfully, the ribs are called ribs. Baby back and spare ribs are not what they sound like. Baby back ribs are also called loin back ribs. You've heard the expression, "Eating high on the hog"? Well, they are talking about the baby back or loin back ribs. Spare ribs aren't really extra ribs. They are the part of the rib closest to the breast bone.
I had some pics of what I'm talking about. As soon as I find them I'll post them to hopefully make this easier to under stand.