National Chocolate Chip Day is celebrated May 14th! Two different varieties of decadent chocolate chip cheesecake on a serving plate, very chocolatey and full of chips! In 1941, Nestle and other competitors started selling chocolate in chip or morsel form. Semi-sweet was the original flavor of chocolate chips. Today they come in bittersweet, semi sweet, mint, white chocolate, dark chocolate, milk chocolate, and white and dark swirled.