Biroldo is a very dark, brownish-red, soft-textured Tuscan blood sausage about 4 inches (20 cm) wide, with lighter-coloured chunks of meat and fat in it. It was traditionally made from parts of the pig, offal such as heart, lungs and tongue, that wouldn't be used for other sausages.
Bratwurst is a specific type of fresh link sausage that originated in Germany. Typically it's made with pork and veal, and seasoned with ginger, nutmeg, coriander, or caraway. Very traditional recipes call for both cream and eggs in their preparation. Bratwurst recipes are different in every region of Germany, and some regions of the United States. Sheboygan-style bratwursts are a popular variation out of Wisconsin.
Sausage is a food usually made from ground meat with a skin around it. Typically, a sausage is formed in a casing traditionally made from intestine, but sometimes synthetic. Some sausages are cooked during processing and the casing may be removed after.
Cotechino Modena or Cotechino di Modena [koteˈkiːno di ˈmɔːdena] (spelled cotecchino or coteghino in some major dialects, but not in Italian) is a fresh sausage made from pork, fatback, and pork rind, and comes from Modena, Italy, where it has PGI status. Zampone Modena is closely related and also has PGI status.
Cotechino Modena or Cotechino di Modena [koteˈkiːno di ˈmɔːdena] (spelled cotecchino or coteghino in some major dialects, but not in Italian) is a fresh sausage made from pork, fatback, and pork rind, and comes from Modena, Italy, where it has PGI status.
Genoa salami is a variety of salami commonly believed to have originated in the area of Genoa. It is normally made from pork, but may also contain veal. It is seasoned with garlic, salt, black and white peppercorns, and red or white wine. Like many Italian sausages, it has a characteristic fermented flavor.
Italian sausage — shocker — is the pork sausage you add to pasta sauces. It comes in a sweet (the same thing as mild) Italian variety, which is primarily flavored with fennel and garlic. Hot Italian sausage contains the same spices, but with a shake or two of chile pepper.
Smoked sausage can be made from ground pork, turkey, beef or a combination of meats -- and they can include any variation of seasonings. Polish kielbasa is traditionally made from ground pork. Some commercial variations of kielbasa are made from ground turkey, but these aren't authentic.