M&M's (stylized as m&m's) are multi-colored button-shaped chocolates, each of which has the letter "m" printed in lower case in white on one side, consisting of a candy shell surrounding a filling which varies depending upon the variety of M&M's. The original candy has a semi-sweet chocolate filling which, upon introduction of other variations, was branded as the "plain, normal" variety. Peanut M&M's, which feature a peanut coated in milk chocolate, and finally a candy shell, were the first variation to be introduced, and they remain a regular variety. Numerous other variations have been introduced, some of which are regular widespread varieties (peanut butter, almond, pretzel, crispy, dark chocolate, and caramel) while others are limited in duration or geographic availability. The candy originated in the United States in 1941, and M&M's have been sold in over 100 countries since 2003. M&M's are products of Mars, Incorporated.
M&M's along with Snickers promoted Transformers: Revenge of the Fallen in 2009. M&M's promoted a special limited edition Strawberry Peanut Butter with the Orange M&M mascot doubled and dressing up as The Twins, Mudflap and Skids on the wrapper.