a shortened cake and an angel cake is an unshortened cake
A light cake made from flour, eggs, sugar and butter. The batter is whisked or creamed to incorporate a lot of air into the mix.
a cake made without shortening and leavened only with eggs
Sponge cake is a type of soft cake based on wheat flour, sugar, baking powder and eggs.Bero flour Home recipes 40th edition Delia Smith's Book of Cakes Sixth Impression 1981. The only fat present is from the egg yolk, which is sometimes added separately from the white. It is often used as a base for other types of cakes and desserts.