Catsup is red stuff. Usually spelled Ketchup. Made from tomato concentrate, high fructose corn syrup, vinegar, corn syrup, salt onion powder, spice and natural flavors. Americans all over America use it on hotdogs and hamburgers, often with mustard and onions. It is a thick sauce Americans also dip french fries into, probably for the vinegar ingredient.
It is often purchased in a 36 oz. (by weight,) bottle and impossible to see in the refrigerator, especially when in the forground with other products behind it.
F.D.