Medicare is a social insurance program administered by the United States government. It provides health insurance coverage to people aged 65 years and over; who meet special criteria, including certain disabilities; or for people of any age with End-Stage Renal Disease. Medicare operates as a single-payer health care system.

 Medicare program allows enrollees the freedom to choose which plan fits their medical and financial needs.  There are four basic plan options:

1. Original Medicare
2. Original Medicare with supplemental insurance (Medigap)
3. Original Medicare with Medigap and a Medicare drug plan (Medicare Plan D)
4. Private Medicare plan:
   1. Health Maintenance Organization (HMO)
   2. Preferred Provider Organization (PPO)
   3. Private-Fee-For-Service Plan (PFFS)
   4. Special Needs Plan

The Medicare program allows enrollees to pick the plan that is most suited to their medical and/or financial needs. There are four basic plans to choose from: Original Medicare, Original Medicare with supplemental insurance (Medigap), Original Medicare with Medigap and a Medicare drug plan (Medicare Plan D), or Private Medicare. If Private Medicare is chosen, there is an additional four options under this plan, which include Health Maintenance Organization (HMO), Preferred Provider Organization (PPO), Private-Fee-For-Service (PFFS) and Special Needs Plan.