Plain version: Medicare is the federal health insurance program for people 65 and older and for certain younger people with a disability or specific illnesses. There are two main ways to receive it, plus private coverage that wraps around it.
Original Medicare = Part A (Hospital Insurance) + Part B (Medical Insurance).
You pay your share as you receive services.
You may use any doctor or hospital in the U.S. that takes Medicare.
There is no yearly limit on out-of-pocket costs.
Drug coverage comes from a separate stand-alone Part D plan.
Medicare Advantage (Part C) is another way to receive Part A and Part B benefits, through a Medicare-approved private company.
To join and stay in a plan, a person must have both Part A and Part B and keep paying the Part B premium. The plan's own premium, if any, does not replace it.
Plans must cover all medically necessary services that Original Medicare covers, and they may add extras such as vision, hearing or dental.
Most plans include Part D drug coverage.
Plans have a yearly limit on out-of-pocket costs for covered services.
Coverage around Medicare:
Medicare supplement insurance (Medigap): private insurance that fills gaps in Original Medicare, such as deductibles, coinsurance and copayments. It works only with Original Medicare; it cannot pay Medicare Advantage costs.
Medi-Cal: California's Medicaid program, based on income and resources.