There are short ribs and long ribs from a cow.
Short ribs are short because they are the ends of ribs, cut off from the rest of the ribs. They are fatty and tough, but produce delicious meat when cooked properly through braising or long, slow barbequing.
The longer ribs are never referred to as “long ribs”; they are called “back ribs.”
Back ribs are more tender, and more expensive.