Health is a condition of mental, physical and social well-being where infirmity and illness are absent. Many different definitions have been employed over the years for different purposes. Modern approaches to health have resulted in the development of many healthcare systems that include prevention, early detection and treatment of the various diseases and ailments. The concept of health has been around since the ancient times when the Greek physician Hippocrates first described the four elements required to maintain health: body, soul, mind and soul. According to him, all of these were related to one another and affected each other to ensure that the human being living a healthy life full of joy and happiness.

As modern society has evolved and the definition of what is health has been expanded to include both the physical determinants and the social factors. It is not uncommon today to find an entire society based on the concept of health. The term is also widely applied to a number of concepts that are used to improve the quality of life and improve the health of the population in general.

One of the primary objectives of public health is the improvement of the overall health of an individual. For this reason, the promotion of better individual behavior is included within the health services. Prevention is always considered to be an important factor in the overall health services.

Prevention can be considered as the modification of individual behavior or the controlling of environmental factors that can promote the onset of disease. The control of environmental factors includes changes in diet and lifestyle, social activities, exercise, and other practices that help people maintain good health. These include the reduction of the presence of toxins in the environment, improving air quality, and ensuring clean drinking water. Public health aims at improving the health conditions of the entire population by reducing the number of life-threatening illnesses. It also involves the monitoring and evaluation of the programs developed to implement these efforts.

Public health programs focus on preventing, diagnosing and treating health problems. Programs may include immunization, surveillance, prevention and education regarding chronic diseases and environmental risk factors. Prevention of acute health problems like heart disease, cancer and diabetes requires identifying the risk factors, tracking the progression of these diseases and developing effective treatment plans. Environmental risk factors that promote the occurrence and development of chronic diseases include exposure to hazardous drugs, smoking, excessive alcohol consumption and other physical activities that increase the heart rate, blood pressure and other cardiovascular conditions.

Mental health refers to the total mental well-being of an individual. Mental health is related to the cognitive, emotional, functional and behavioral qualities of an individual. A well-maintained mental health facilitates coping with stress, improving academic performance, maintaining job performance, minimizing health complications and averting potential disabilities. Public health approaches to the promotion of mental health through the promotion of social networks, support for the development of mental health, research and service provision for those who suffer from mental illness and other physical disorders. The National Institute of Mental Health notes that mental disorders affect nearly 50 million Americans and cost millions of dollars in medical care each year.