Medicare Part D is simply insurance for your medication needs. You pay a monthly premium to an insurance carrier for your Part D plan. In return, you use the insurance carrier's network of pharmacies to purchase your prescription medications. ... Your Part D insurance card will be separate from your Medigap plan. During my career, I noticed that people aging into Medicare had limited access to easy-to-understand information on Medicare. Medicare can be complicated but it can also be relatively simple if you know where to get the information you need. So the goal of this book is to provide quick access to important information on things like Medicare enrollment periods, Medicare Supplements, Medicare Advantage, and Medicare Prescription Drug Plans.