Maker: Mars, Incorporated

Maybe it's because they'll melt if you don't consume them in under 20 seconds. Maybe it's because they're small enough to toss into your mouth with abandon. Maybe it's just that fragile outershell of chocolate, and how enjoyable it is to gnash your teeth through 50 of them at once. There is no one reason; there are many. M&Ms, we're in awe of your myriad wonders.