I thought about calling this segment BBQ 101, but since I intend to get more in depth than your standard Wikipedia page, this is BBQ 801...a graduate level class. This course will take you from the butcher shop, to the smoker, onto your table and into your pie-hole. There's no need for the subject matter to travel any further than that.
Our first subject takes us to the butcher shop to explore the carcasses of our tasty friends, the cow and the hog. We'll start with the brisket. A whole brisket, or packer cut, is made up of two distinct muscles separated by a layer of fat. The flat cut (deep pectoral or pectoralis profundus) is the leaner of the two and the point cut (superficial pectoral) is fattier and because so it's considered more flavorful. Most joints smoke the full brisket, but first timers at home would be wise to start with the flat cut for a consistent thickness. A full brisket should be separated before carving as the muscle fibers of the point and flat run in different directions. A study by the University of Nebraska goes into the details of the tenderness of different beef cuts.
The brisket is located in the front quarter of the cow, just above the front legs as shown in this diagram:
The brisket is a fatty piece of meat in a region of the cow that gets quite a workout, so its tough. What makes it tough? Loads of muscle fiber binding collagen which needs to be cooked low and slow in order to melt into silky gelatin, but we'll get further into that in future 801 classes. The other popular portion of the beeve for Texas BBQ are the ribs. I trust that locating these is not a challenge, but the point here is that the meat connected to the ribs gets much less exercise, and is therefore naturally more tender. Usually, little meat is left on the beef rib, because the meat connected to it is trimmed off into expensive ribeyes. Much more popular throughout the country are pork ribs. Refer to the diagram below of a whole hog:
You'll notice the shoulder in the diagram, which is the Carolina BBQ standard, but we're talking Texas 'cue. Pork ribs someitmes play second fiddle to the brisket in Texas, but they're offered in every joint I've visited with the exception of the Hot Pit in Del Rio. Pork ribs come in three categories; baby backs, spare ribs and St. Louis style ribs. Baby backs come attached to the pork tenderloin, so like beef ribs, they can sometimes be light on meat and heavy on bone. The term baby back insinuates nothing about the age of the pig. Spare ribs start just below the baby backs, and continue down to the fatty ends of the ribs bones. St. Louis style ribs are simply spare ribs with the rib tips carved off. See the diagram below:
The further down the rib, the fattier the meat gets. Again, these muscles get very little exercise, so the meat is naturally tender, and the thinner meat takes less time to smoke than the larger beef brisket. Thin or not, the excessive amounts of fat still require the cooking to be low and slow to properly render the fat, and let it melt into the meat. I just don't suggest you slice it like the photo below.
I hope this gets you familiar with your favorite meaty parts, and I hope everyone understands why I didn't bother with a diagram showing where sausage comes from. Who really wants to know that? Next time we'll cover the science of meat preparation before it ever gets to the fire. Class dismissed.