Guidelines generally give recommended amounts measured in grams (g) of pure alcohol. Some guidelines also express alcohol intake in units or standard drinks when recommending maximum alcohol intake. The size of a standard drink varies widely, as does the recommended maximum number of drinks per day or week, among the various guidelines.[8][9] The amounts listed are not meant as recommendations for how much alcohol a drink should contain, but rather to give a common reference that people can use for measuring their intake, though they may or may not correspond to a typical serving size in their country.[10]