Medicare was established when President Lyndon B. Johnson signed the Medicare and Medicaid legislation into law on July 30, 1965. The program began offering coverage in 1966, initially providing health insurance primarily for United States citizens ages 65 and over. It originally included only Medicare Parts A (hospital insurance) and B (medical insurance). Since then, Medicare has expanded to include additional parts and coverage for certain younger people with disabilities and chronic conditions. The program enrolled about 19 million people in its first year and has grown significantly since then.
