M&M’s are among the most recognizable candies in the world, with their colorful shells, chocolate centers, and the tiny letters printed on each piece. Behind those two letters is a story that began in the early 1940s, when Forrest Mars Sr. and Bruce Murrie formed a partnership that linked the Mars candy company with access to Hershey’s chocolate. Introduced in 1941, M&M’s quickly stood out as a convenient, portable treat, thanks to a hard sugar coating that helped the chocolate resist melting. This simple design would prove especially valuable as the candy found its way into the hands of American military personnel during World War II, when foods that were easy to carry and slower to melt were especially prized. The initials M&M themselves stand for Mars and Murrie, preserving the names of the two families whose cooperation launched the brand.

The earliest M&M’s looked different from the multicolored assortments found today, starting out with brown shells and a small letter on each piece. As the candy grew in popularity, new colors were added, helping it appeal to both children and adults. Over time, the company expanded the line with peanut M&M’s, peanut butter versions, and other flavors, along with seasonal colors, special packaging, and creative advertising. Although Bruce Murrie’s partnership eventually ended and Forrest Mars gained control, the basic idea remained the same: chocolate protected by a candy shell. From movie theaters and parties to cookies and desserts, M&M’s spread worldwide, and the two letters on every piece now recall the collaboration that helped create a long-lasting candy favorite.