The human life cycle may be divided into varying amounts of stages. The five main stages of the life cycle are birth, infancy, childhood, adolescence and adulthood.
Birth begins with fertilization and usually ends after approximately 40 weeks of pregnancy. This is considered the stage of potential, as the unborn child may become anything. The next stage of the life cycle is infancy. During infancy, babies begin exploring the world around them with energy and interest. Throughout early and middle childhood, kids develop an inner self with a vivid imagination. In late childhood, children learn various skills that help them cope with practical and social situations. During adolescence, teens undergo puberty and experience dramatic changes both physically and emotionally. Finally, during adulthood, people become independent. Young adults make decisions that affect the rest of their lives, such as picking a college and a career. People get married and have children, which allows the human life cycle to go on and repeat itself. Late adulthood ends with the elderly stage. This stage is often marked by retirement and sharing wisdom gained through life experiences to prepare youths for the later stages of this cycle. The human life cycle ends with dying and death.