What is Medicare?
Medicare is insurance you get when you turn 65 or when you retire. There are some people that get it earlier but for the most part it is for seniors.
Medicare A & B
These are the parts of Medicare that you think of when you think of Medicare. Medicare A is free for most people. Medicare B is paid through your social security benefits. These two parts cover 80% of your medical costs but almost not medications.
Medicare C aka Medicare Advantage
To fill the gap you can get Medicare C and that usually contains medical and prescription coverage. Many plans also cover dental and vision. Sometimes these plans are limited in the number of doctors you can see.
Medicare D aka prescription coverage and Medigap aka Supplemental
In this option you also get the gap in coverage covered. More doctors accept this option but it can sometimes be more expensive than Medicare C.