Public health is “the science and art of preventing disease, prolonging life and promoting human health through organized efforts and informed choices of society, organizations, public and private, communities and individuals.” Analyzing the health of a population and the threats it faces is the basis for public health. Public health professionals work to prevent problems from happening or recurring through implementing educational programs, recommending policies, administering services, and conducting research. Public health also works to limit health disparities by promoting healthcare equity, quality, and accessibility. You can look at public health narrowed down to any population — from a neighborhood, country, or our entire planet.
Many factors affect public health, and people are unlikely to be able to directly control those factors. Social and economic environment, as well as physical environment, can be determine their quality