Breast milk usually refers to the milk prouced by a human female which is usually fed to infants, toddlers, and young children by breastfeeding. It provides the primary source of nutrition for newborns before they are able to eat solid food and digest a wider variety of food. Breast milk is fed to the infant by a variety of methods: breastfeeding, baby bottle, cup and/or spoon, supplementation drip system, and nasogastric tube.