Rotwurst is a German blood sausage, which is usually sliced and served on pieces of bread. The name depicts the color (red).
A German blodd sausage (Blutwurst) is made out of diced bacon and calf's or pig's lungs. It is seasoned with cloves, mace and marjoran. It is often served with potatoes and cooked apples.
A Blutwurst interlaced with bits of tongue. It consists of pork fat, pig's blood and tongue and does not contain any cereal additives. It usually comes pre-sliced and is eaten cold on crusty bread.