Medicare Part C is Medicare's program for private health plans, commonly called Medicare Advantage. If you join a Medicare Advantage plan it will replace your Medicare Part A and Part B coverage (Original Medicare). It's called Medicare Advantage because plans may include extra benefits that Original Medicare does not cover, such as a prescription drug plan, and routine dental, vision, and hearing care.
Medicare Part D are stand-alone prescription drug plans. These plans work with Original Medicare and with Medicare Advantage plans that do not include prescription drug benefits. Plans help with the cost of prescription medications.
In Understanding Medicare in 4 Easy Steps we explain all of the different costs with Part C and Part D plans, and how to choose the best plan for your personal health and financial situation.