What is Medicare, and Who is Eligible? Medicare is a federal health insurance program for adults 65 years or older, or individuals under 65 with certain disabilities or end-stage renal disease. The program is divided into several parts, each of which covers specific healthcare services. Medicare Part A covers Inpatient care, Hospital stays, Hospice Care, and some Skilled Nursing Facility stays. Part B covers Doctor visits, Outpatient care, Preventative services, and some Medical equipment. Part C, or Medicare Advantage, is an alternative to the traditional Medicare plans offered by private insurers. Finally, Part D covers prescription drugs.