Spoiler alert! The founders of the company that invented this classic candy were Messrs. Mars & Murrie. It's their combined initials. They started selling little bags of these new candies all over the US and soon many people started to buy bulk M&M's.
The color scheme for M&Ms has changed over the years. Blue is a relatively new color for M&M's in bulk. Not too long ago there was a light brown color in the mix, along with the still-used dark brown candies. Back in 1941, they never could have anticipated that they would sell candy via computers over something called the internet. But so it is that now you can buy bulk M&M's right from your home and have them delivered quickly and fresh to your door.