Public health is an important field that encompasses many areas of study. The five core areas of public health are epidemiology, biostatistics, health services, environmental health, and social and behavioral sciences. Epidemiology is the study of health and illness in populations, and it involves looking at the causes and risk factors of diseases, as well as their effects on individuals and populations. Biostatistics is the use of mathematical and statistical methods to analyze data related to health and disease. Health services involve the delivery of health care services to communities and individuals. Environmental health focuses on the effects of environmental factors on human health, such as air and water pollution, hazardous substances, and climate change. Finally, social and behavioral sciences look at how social, cultural, and economic factors impact health outcomes. Together, these five core areas of public health work to understand and improve the health of individuals and populations.

Public health is a field dedicated to promoting the health and wellbeing of communities. It focuses on the prevention of disease and injury, and improving the health of individuals and the population as a whole. The roles of public health include disease surveillance and prevention, health promotion, health policy development, health research, and health and safety regulation. Public health professionals also provide direct service to patients and communities, such as providing health education and screenings and providing medical care in underserved communities. Finally, public health also works to ensure access to healthcare and to advocate for health-related policy changes.