Today (March 6th) is National Oreo Cookie Day! Who doesn't love Oreo cookies with a tall glass of cold milk? According to National Day Calendar, the Oreo was first trademarked as the Oreo Biscuit in 1912. The modern design was developed in 1952. More than 450 billion Oreos have been sold worldwide. Whether you like to pull 'em apart, and lick the creme filling, or dip 'em in milk, Oreos are America's favorite cookie. Bon Appetit!