Public health is the science of protecting and improving the health of people and their communities. It focuses on promoting healthy lifestyles, researching disease and injury prevention, and detecting and responding to infectious diseases. Public health professionals work to ensure that everyone has access to essential health services and information. Through various initiatives, such as vaccination programs and health education campaigns, public health aims to reduce health disparities and improve overall quality of life. Organizations like the World Health Organization and Centers for Disease Control and Prevention play crucial roles in shaping public health policies and practices worldwide.