Medicare does not cover everything, leaving significant gaps in health-care coverage. Specifically, Original Medicare (Part A and Part B) typically does not cover outpatient prescription drugs, most long-term care (custodial care), deductibles and co-pays beyond a certain point without supplemental insurance, most dental care, routine vision care, hearing aids, or medical care overseas except in very limited circumstances. While Medicare Part A and Part B cover a large portion of medical expenses after age 65, including inpatient hospital stays, skilled nursing facilities, surgery, hospice care, home health care, doctors’ visits, outpatient care, preventive services, and some medical equipment, it's crucial to understand these uncovered areas. Supplemental insurance policies like Part D, Medicare Advantage plans, Medigap policies, or long-term care insurance can help cover these additional costs and prevent unexpected medical bills in retirement.