Fries, usually referred to as French FRIES, are a popular SIDE dish and sidedish in many countries. They are made from potatoes that are cut into thin strips and then deep-fried. FRIES are usually served hot with condiments such as ketchup, mayonnaise, or vinegar. The term 'FRIES' is derived from the French word 'frites, ' which means 'to fry.' FRIES are a staple of fast food restaurants and are also a popular snack food.