Grade A milk is produced under specific sanitary conditions–on the dairy farm and in the dairy plant–that are established and regulated by the Food and Drug Administration (FDA).  All fluid milk sold for human consumption in the U.S. is Grade A.  Grade B milk, which does not meet these standards, is regulated by the U.S. Department of Agriculture (USDA), and can be used in products such as cheese, butter, and non-fat dry milk.