Health insurance is a form of insurance that helps pay for medical services, such as doctor visits, tests, and hospitalization. Private insurance companies and government agencies, like the Medicare and Medicaid programs in the United States, are the primary providers of health insurance. Health insurance ensures that people can afford medical care and protects the individual from being overburdened with enormous health care bills. Private companies charge a monthly fee, or premium, for health care coverage. Government-based health insurance is usually free and sometimes based on certain criteria, such as age or income.

Health insurance is a relatively recent phenomenon, having emerged primarily during the course of the twentieth century. As early as 1883, Germany had established a government-sponsored health services system to provide care for low income people who could not afford it. Still, as recently as 1929, no insurance was available to cover the costs of...