Clam chowder is a source of controversy on the East Coast. Even within New England, there are different varieties of clam chowder, though all are different from Manhattan clam chowder, which uses tomatoes rather than the creamy broth popular to the north. Most cooks agree that quahogs, also known as "chowder clams," are the best seafood choice, especially if you can get them fresh, but there's some disagreement about whether the addition of salt pork or bacon brings the best flavor.
Clam chowder has a long history. By the early 19th century, the creamy, warming soup was already popular in Boston. Herman Melville sang the praises of clam chowder in his famous book "Moby Dick," solidifying the dish's image as a warming meal for chilled seafarers.