In almost all foods that you eat contain calories. Calories are simply another fancy word for 'energy'. The body needs the calories in the foods to use as energy. Without calories, we wouldn't be able to even go out and have fun.
For those of you who like to know the varying amount of calories in different foods and drinks, the following links, which has an arsenal of pages devoted to laying out the calories in foods, lead to help you along. This online guide can be of great help when planning your diet - or whenever you think you may have had too much to eat, or even too little to eat.