There are two main types: butter and foam. Butter cakes are named because they contain either butter, margarine, or shortening, resulting in a heavier texture. Examples of butter cake include carrot cake, pound cake, and marble cake. Foam cakes are light pastries that derive their fat content from the eggs. They are fluffier due to the air that is beaten into the egg whites and has a low-fat content. Examples include angel food cake, sponge cake, and meringue.