The science and practice of feeding babies through the first year of life to support rapid growth, brain development, and immune protection. Exclusive breastfeeding for around six months is the global recommendation, with breast milk providing ideal nutrition plus antibodies and growth factors. Where breastfeeding is not possible, regulated infant formula offers a safe alternative with tightly controlled composition. From about six months, complementary foods of increasing texture and variety join milk feeds. Nutrients of special concern include iron, zinc, iodine, vitamin D, and long-chain fatty acids. Strict safety and compositional standards govern all commercial infant foods.