Medicare is a federal health insurance program that provides coverage to individuals over the age of 65 and those with certain disabilities. There are four parts to the Medicare program: Parts A, B, C, and D. Part A covers inpatient care in Hospitals , Hospice care, and some Home Health Care . Part B covers Outpatient Care , such as Doctor visits, Preventive services, and Medical Equipment . Part C , also known as Medicare Advantage , is an alternative to traditional Medicare that covers both Part A and Part B benefits and most plans include a Part D Rx Plan. Part D covers Prescription Medications . To be eligible for Medicare, individuals must be either 65 years or older, have certain disabilities, or have been diagnosed with end-stage renal disease (ESRD).