The candy shells, each of which has the letter "m" printed in lower case on one side, surround a variety of fillings, including milk chocolate, dark chocolate, crisped rice, mint chocolate, peanuts, almonds, orange chocolate, coconut, pretzel, wild cherry, and peanut butter. M&M's originated in the United States in 1941, and are now sold in over 100 countries. They are produced in different colors, some of which have changed over the years. The difference between the different colored M&Ms is the dye added to the outer coating.
