What does “Serving Size” mean on a food label?

A serving size is the amount of food in one serving of a product.

1 serving of this product = 4 cookies (30 grams)

The nutrition facts on a label represent the amounts in one serving.

4 cookies contain:
220 calories (110 calories from fat)
12 grams (g) of fat (6g saturated and 0.5g trans)
10 milligrams (mg) of cholesterol
70 milligrams (mg) of sodium
25 grams (g) of carbohydrates (1g fiber and 20g sugar)
3 grams (g) of protein