Medicare is a federal health insurance program for people ages 65 and older and people with certain disabilities.
The Medicare program is divided into four separate parts:
- Medicare Part A: Hospital Insurance
- Medicare Part B: Medical Insurance
- Medicare Part C: Private Health Plans (Medicare Advantage)
- Medicare Part D: Private Prescription Drug Plans
Parts A and B, known as Original Medicare, work with Part D but they are not compatible with Medicare Advantage plans, which completely replace Part A and B coverage, and may include Part D.
A fifth part, called Medigap, is not part of the Medicare program but is regulated by both the Centers for Medicare & Medicaid Services (CMS), the agency that administers Medicare, as well as state insurance boards. Also called Medicare supplements, these private insurance policies help cover some of the gaps in Original Medicare.