Child development is a general term that takes into account all areas of a child's growth, including physical, intellectual, emotional, moral, social, psychological, and sensory and motor development.

All children develop at different rates in different areas, and the growth of a child is a complex process of becoming older, bigger, and more accomplished. A child may lag behind his peers in physical development, for instance, but function at above average in intellectual or emotional growth. How quickly a child develops physically, mentally and emotionally depends on many things, including economic, social, genetic, and environmental factors.

Physical growth is a continuous process, and occurs at varying rates within discrete stages: infancy (from birth to 3 years), followed by the preschool period (from 3 to 6); early childhood from age 6 to 9, and later childhood from 9 to 12. These periods are followed by early and late adolescence.

Psychologically, an infant grows from...