"these are examples of partitive article (du, de la, de l', des, de), which is the third type of article in French; the others are the definite article (le, la, les, l') and the indefinite article (un, une, *des); the partitive is used to indicate a certain amount or quantity, but not the whole, of something. In other words, it indicates part of a greater whole. It also indicates an unspecified number of something."