Medicare Advantage
Medicare Advantage (Medicare Part C, prior to 2003 also Medicare+Choice or M+C) is a type of health plan in America offered by private companies as part of the original Social Security Act of 1965 that created Medicare. It permits a private insurance option that wraps around traditional Medicare. Medicare Advantage plans attempt to fill some coverage gaps and offer alternative coverage options.
Under Part C, Medicare pays a plan operator a fixed payment for each enrollee. The operator then pays for their medical expenses. Traditional Medicare directly compensates providers on a fee-for-service basis. Plans are offered by integrated health delivery systems, labor unions, non profit charities, and health insurance companies, which may limit enrollment to specific groups of people (such as union members).