Chocolate Milk Shake Day is celebrated on September 12, 2017. A milkshake is a sweet, cold beverage which is usually made from milk, ice cream or iced milk, and flavorings or sweeteners such as fruit syrup or chocolate sauce. Outside the United States, the drink is sometimes called a thickshake or a thick milkshake or in New England, a frappe, to differentiate it from other less-viscous forms of flavored milk.
Full-service restaurants, soda fountains, and diners usually prepare and mix the shake "by hand" from scoops of ice cream and milk in a blender or drink mixer using a stainless steel cup. Many fast food outlets do not make shakes by hand with ice cream. Instead, they make shakes in automatic milkshake machines which freeze and serve a premade milkshake mixture consisting of milk, a sweetened flavoring agent, and a thickening agent. (With material from: Wikipedia)