Stress is a normal part of life that can be caused by both external factors like work deadlines or arguments, and internal factors like beliefs and expectations. When a person experiences stress, their body activates a stress response with physical effects like increased heart rate and sweating. While moderate short-term stress can be helpful, long-term stress takes a toll physically and mentally if not managed. The document provides tips for managing stress through relaxation techniques, exercise, organization, changing one's attitude, and focusing on self-care.