Every time your baby moves, she's practicing ways to make her body act the way she wants it to. Infants develop from top to bottom. Head movements come first, then neck muscles begin to strengthen.
Development continues on to the arms, hands, legs and feet.
For example, once your baby learns to control her head and neck, she's on her way to mastering sitting. How and when a baby learns to crawl and then walk is a complicated matter. Everything in his surroundings plays a part. The relationship between what's around him and how he's allowed to interact with his environment are vital to his development. Experts have learned that babies who receive lots of physical and visual stimulation early on will crawl and walk earlier than babies who are often confined to a crib or playpen.