Coating chocolate with a hard shell began with M&Ms during worldwar II. Coated candies were easier to transport because the coating prevented them from melting. Making coated candies is an interesting process. First the chocolate centers are formed in little molds. These chocolate centers are then placed in a large rotating drum that looks a bit like a cement mixer. Temperature controls on the drum maintain a low enough temperature to prevent the chocolate from softening. While rolling around in the drum, the chocolate are sprayed with sugary liquid that hardens into the white candy shell. Since the chocolates are constantly rotating, they do not clump together while wet with the sugary liquid. Once the white candy shell has hardened, a second, colored, sugar liquid is sprayed into the drum. Once the color coating dries, the colored candies are removed from the drum by pouring them onto a conveyor belt where each candy fits into one of thousands of candy shaped depressions. The belt vibrates gently to seat the candies into the depressions. Once they are organized on the belt, they proceed through a machine that gently imprints a maker's mark onto each candy with edible ink.