A lot of people use yellow cake and white cake interchangebly, but they are not one and the same. A recent post on Chowhound spells out the difference between yellow and white cake. The two main differences are eggs and flour. For yellow cakes, most recipes call for whole eggs, and for white cakes only egg whites are used. Another difference is flour. For white cakes, a cake flour is often used whereas all purpose flour can be used for yellow cake.