$Medicare is a federal health insurance program in the United States that primarily serves individuals aged 65 and older. It also covers certain younger people with disabilities and those with specific medical conditions, such as End-Stage Renal Disease or Amyotrophic Lateral Sclerosis. Medicare helps pay for various healthcare services, including hospital stays, doctor visits, and prescription medications. The program is divided into different parts: Part A covers hospital insurance, Part B covers medical insurance, and Part D provides prescription drug coverage. Beneficiaries can choose to receive their benefits through original Medicare or through Medicare Advantage plans, which are offered by private insurance companies.