Speaking of meat, what is corned beef? How about pastrami?
Both start with the same cut of meat, and that is a primal cut called the brisket. The pectoral muscles between the steer's front legs. This is a rough, tough cut of meat with a lot of connective tissue in it so unless really beaten down with heat, it is almost inedible. The brisket (called a packer brisket when it is still whole) is a large piece, made of two sub cuts, the 'flat' and the 'point'; the flat is relatively lean while the point has quite a lot of intramuscular fat. The whole brisket or packer cut briskets are almost exclusively used for BBQ where they are both smoked and cooked for a long time at very low temperatures so the connective tissue is broken down. Brisket can be an excellent piece of beef but it does not forgive lousy technique. It is also a large cut, weighing in the range of 12 to over 20 lbs.
Corned beef is a piece of beef, almost always the brisket, that is brined and cured in both table salt as well as 'curing' salt or sodium nitrite. The table salt used a long time ago was in the form of very large crystals or "corns" of salt, hence the name corned beef (there is no corn used in the process). The sodium nitrite is pink in color and gives the corned beef its dark pink color. The brining / curing process takes around 8 days and at the end you have a piece of brisket, usually the flat or point alone as they are separated before curing, that is cured, salted and still raw. It is typically cooked by boiling for a long time and has a unique taste.
Pastrami is a little more involved and starts off with a piece of brisket, usually the flat, that has already been 'corned'. So to make pastrami, one needs corned beef rather than a raw piece of beef as it was butchered. The corned beef cut is covered in spices (no salt- it is already quite salty) which are almost always pepper based. Then the beef is smoked at low temps., perhaps 225 to 275F for at least several hours and often closer to a full day. It can be consumed right out of the smoker but it is more commonly left to cool completely and then sliced cold and either eaten that way or re- heated by steam if done in a restaurant that specializes in that type of product. Again, it has the pink color from curing but is somewhat darker than the original corned beef and again is a unique flavor not really similar to anything else including the corned beef it was made from.
Barbeque started in the Caribbean and maybe also in Florida. Europeans picked it up in a big way when they got to the new world. As old world people moved west in America, they took barbeque with them. But it was done using pork and when BBQ got to Texas it started to include beef, again usually the rougher, tough, other wise pretty useless cuts such as brisket. BBQ'ing beef came with its own problem though in that the meat did not have enough fat to fully cook without tending to dry out so they started to use what is called the 'Texas crutch', which is smoking the meat until it reaches between 150F and 170F internal temp. and then wrapping it in foil or paper and putting it back on the pit to finish cooking without smoking as it is now covered. Most cuts of meat are brought up to just over 200F but they slow way down in temp. rise around 160F, which is called the 'stall' and wrapping it pushes it through this stall to the final temperature. So brisket is a long, two step process to smoke, and that does not include prepping the meat which takes a lot of trimming or injecting and / or seasoning the outside (called the 'rub').
All three ways to use a brisket can result in some really desirable end products but none are quick or easy like, say, a piece of sirloin is to prep. and cook. And the full packer brisket looks like someone cut it out of the steer's carcass with a dull chainsaw. But given the time and a bit of learning, it does make a very nice finished meal that is not really like any other cut or process type of beef.