A hot dog is a dish consisting of a grilled, steamed, or boiled sausage served in the slit of a partially sliced bun. The term hot dog can refer to the sausage itself. The sausage used is a wiener or a frankfurter. The names of these sausages commonly refer to their assembled dish. Hot dog preparation and condiments vary worldwide. Typical condiments include mustard, ketchup, relish, onions in tomato sauce, and cheese sauce. Other toppings include sauerkraut, diced onions, jalapeños, chili, grated cheese, coleslaw, bacon and olives. Hot dog variants include the corn dog and pigs in a blanket. The hot dog's cultural traditions include the Nathan's Hot Dog Eating Contest and the Oscar Mayer Wienermobile.

Pigs in a blanket in the United States is a small hot dog or other sausage wrapped in pastry similar to a sausage roll in the UK, it is commonly served as an appetizer in the United States. The similarity in name with that of the UK dish pigs in blankets, which is a sausage wrapped in bacon, sometimes causes confusion.