ABSTRACT
Biological changes and social demands define social roles and typical life events in people’s lives. Life span specifies the temporal order of life stages, such as childhood, adolescence, and adulthood, whereas life course specifies social role demands at different stages. In order to understand people’s lives holistically, one should simultaneously consider physical maturation, psychological development, social-role demands, and life context. Life-span developmental trajectories for biological, cognitive, personality, and social functioning are intertwined with each other and with age-graded life-course trajectories in, for instance, family, education, and work.
