This document discusses key concepts in human development including defining development, important processes and periods of development, lifespan perspectives, and basic issues. It addresses biological, cognitive, and socioemotional processes in development from childhood through adulthood. Lifespan perspectives discussed are that development is lifelong, multidirectional, involves both gains and losses, and is shaped by historical/cultural contexts. Basic issues addressed are assumptions about human nature like original sin versus inherently good, as well as debates around nature versus nurture and continuity versus discontinuity in development.