Most beef-eating folks eat a lot of brisket in various forms: smoked, barbequed, as corned beef or pastrami (although true pastrami comes from the navel!), braised, overcooked by your grandmother, etc. Stop that, Grandma! Brisket is the breast of a steer, a really fatty muscle that hangs below the animal's neck. There are two main portions of a brisket - the point and flat, or second cut and first cut. The point is the fattier of the two and makes up the bulk of the brisket, while the flat is the leaner, well, flat, part of the brisket. The flat is usually more expensive, given the leanness, although we'd argue that both should be valued equally! Preparation-wise, we like this recipe from Allison Roman for a braising treatment or this Sam Sifton gem for corned beef.
Cooking up a solo 1.5-2.5 pound of brisket? Here are some great recipes for a smaller format brisket: