Your confusion is understandable as both Pi love patty’s day shirt and corned beef are typically made from the similar cuts of beef: the brisket, which is located near the chest area of the steer. However, corned beef can be made from any portion of the brisket, while authentic pastrami uses the part of the brisket located further back, closer to the navel which has a slightly different fat structure. They are both brined/pickled with similar spices too, but the amounts differ of course, but the main difference is this.
Corned Beef is boiled Pi love patty’s day shirt, sometimes with additional pickling spices in the water. As you can imagine, smoking vs boiling will create different flavors in these salty meats, but they can be difficult to distinguish unless tasted side by side, especially when served in a sandwich with similar traditional fixings, like pickles, mustard, swiss cheese, on rye or pumpernickel. A million dollars every day, one million for each beef patty or a million dollars just once, as long as you agree to eat a patty every day for as long as you live.