The author seeks to describe functionally the nature of human stress and its link with a wide variety of issues or activities. It affects health, performance, wellness, crime, violence, positive affectivity, productivity, well¬being (happiness), family life, marriage, learning activities, problem-solving, decision making, diseases of lifestyle, ageing, etc. To ensure effective learning and understanding, an outline of the origin of human stress and stress-related key concepts is included. Individual differences play an important role in the experience, perception, reaction and managing of stressors. We are stressed in accordance with our personality, lifestyle, values, beliefs, and/or expectations of outcomes. Stress affects people from all walks of life differently and is inevitable.