Childhood is the age span ranging from birth to adolescence. According to Piaget's theory of cognitive development, childhood consists of two stages: preoperational stage and concrete operational stage. In developmental psychology, childhood is divided up into the developmental stages of toddlerhood (learning to walk), early childhood (play age), middle childhood (school age), and adolescence (puberty through post-puberty). Various childhood factors could affect a person's attitude formation.
Early childhood is a stage in human development. It generally includes toddlerhood and some time afterwards. Play age is an unspecific designation approximately within the scope of early childhood. Some age-related development periods and examples of defined intervals are: newborn (ages 0–5 weeks); infant (ages 5 weeks – 1 year); toddler (ages 1–3 years); preschooler (ages 3–5 years); school-aged child (ages 6–11); adolescent (ages 12–17).
Living organisms including humans are social when they live collectively in interacting populations, whether they are aware of it, and whether the interaction is voluntary or involuntary.
Perhaps there lives some dreamy boy, untaught In schools, some graduate of the field or street, Who shall become a master of the art, An admiral sailing the high seas of thought Fearless and first, and steering with his fleet For lands not yet laid down in any chart.
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