Sugar is a carbohydrate. There are three types of carbohydrates: starches or complex carbohydrates, sugars or simple carbohydrates, and fiber. Table sugar, or sucrose, is an example of the carbohydrate type called sugars.
There are two types of sugars: those that occur naturally, such as in fruit and milk, and those that are added as sweeteners. Table sugar and sugar cane syrup fall in the latter group. The sugar in milk is called lactose, while the sugar that occurs naturally in fruit is called fructose. In nutritional labeling, they are often expressed in grams. All types of sugars are carbohydrates.