<P> In the United States, Medicare is a national health insurance program, now administered by the Centers for Medicaid and Medicare Services of the U.S. federal government but begun in 1966 under the Social Security Administration . United States Medicare is funded by a combination of a payroll tax, premiums and surtaxes from beneficiaries, and general revenue . It provides health insurance for Americans aged 65 and older who have worked and paid into the system through the payroll tax . It also provides health insurance to younger people with some disability status as determined by the Social Security Administration, as well as people with end stage renal disease and amyotrophic lateral sclerosis . </P> <P> In 2015, Medicare provided health insurance for over 55 million--46 million people age 65 and older and 9 million younger people . On average, Medicare covers about half of the healthcare charges for those enrolled . The enrollees must then cover their remaining costs either with supplemental insurance, separate insurance, or out of pocket . Out - of - pocket costs can vary depending on the amount of healthcare a Medicare enrollee needs . These out - of - pocket costs might include deductibles and co-pays; the costs of uncovered services--such as for long - term, dental, hearing, and vision care--and supplemental insurance premiums . </P> <P> Medicare is further divided into parts A and B--Medicare Part A covers hospital (inpatient, formally admitted only), skilled nursing (only after being formally admitted for three days and not for custodial care), and hospice services; Part B covers outpatient services including some providers services while inpatient at a hospital . Part D covers self - administered prescription drugs . Part C is an alternative called Managed Medicare by the Trustees that allows patients to choose plans with at least the same benefits as Parts A and B (but most often more), often the benefits of Part D, and always an annual out of pocket spend limit which A and B lack; the beneficiary must enroll in Parts A and B first before signing up for Part C . </P> <P> The name "Medicare" was originally given to a program providing medical care for families of individuals serving in the military as part of the Dependents' Medical Care Act, which was passed in 1956 . President Dwight D. Eisenhower held the first White House Conference on Aging in January 1961, in which creating a health care program for social security beneficiaries was proposed . In July 1965, under the leadership of President Lyndon Johnson, Congress enacted Medicare under Title XVIII of the Social Security Act to provide health insurance to people age 65 and older, regardless of income or medical history . Johnson signed the bill into law on July 30, 1965 at the Harry S. Truman Presidential Library in Independence, Missouri . Former President Harry S. Truman and his wife, former First Lady Bess Truman became the first recipients of the program . Before Medicare was created, approximately 60% of people over the age of 65 had health insurance, with coverage often unavailable or unaffordable to many others, as older adults paid more than three times as much for health insurance as younger people . Many of this latter group (about 20% of the total in 2015) became "dual eligible" for both Medicare and Medicaid with passing the law . In 1966, Medicare spurred the racial integration of thousands of waiting rooms, hospital floors, and physician practices by making payments to health care providers conditional on desegregation . </P>

Th part of medicare that is the hospital insurance portion is