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 while others are limited in duration or geographic availability. M&M's are the flagship product of the Mars Wrigley Confectionery division of Mars, Incorporated.
The candy originated in the United States in 1941, and M&M's have been sold in over 100 countries since 2003. They are produced in different colors, some of which have changed over the years. The candy-coated chocolate concept was inspired by a method used to allow soldiers in the Spanish Civil War (1936–1939) to carry chocolate in warm climates without it melting. The company's longest-lasting slogan reflects this: "Melts in your mouth, not in your hand." A traditional milk chocolate M&M weighs about 0.91 grams / 0.032 ounces and has about 4.7 calories (kcal) of food energy (1.7 kcal from fat). Despite commonly reported misinformation online, each colored M&M does not have a different flavor and all possess the same chocolate taste.