Maslow's Hierarchy of Needs outlines 5 stages that a person must progress through to feel happy and motivated: 1) Physiological needs like food and shelter, 2) Safety needs like security, 3) Love and belonging through relationships, 4) Esteem through achievement and respect, and 5) Self-actualization by fulfilling one's potential. The stages are hierarchical, meaning lower needs must be met before progressing to higher levels.