Pastry Cakes
Pastry cakes can best be described as sweet, decadent, rich and in general, pastries are smaller in size than cakes, and they usually have a more intricate shape. Cakes, on the other hand, are often round or square and can be quite large. Pastries typically contain more sugar and butter than cakes and they often have a crispy crust.
Butter-cream frostings (using butter, cream, confectioners [powdered] sugar and flavourings) began replacing traditional boiled icings in first few decades 20th century. In France, Antonin Careme [1784-1833] is considered THE premier historic chef of the modern pastry/cake world.