This document provides an overview of the four parts of Medicare (Parts A, B, C, and D) and summarizes their key features. It explains that Part A covers hospital insurance, Part B covers medical insurance, Part C is the Medicare Advantage program offered by private insurers, and Part D is the prescription drug plan. It provides details on eligibility, covered benefits, premiums, and enrollment periods for each part. It also summarizes other Medicare options like Medicare Supplement plans, Medicare-Medicaid plans, and Medicare beneficiary protections.