ThinkProgress had an interesting article on the 50th anniversary of Medicaid and Medicare. President Lyndon B. Johnson signed Medicaid and Medicare into law 50 years ago today. Simply, Medicaid provides health insurance for poor Americans, and Medicare provides insurance for Americans over 65 years old. In 1966 a large portion of seniors were uninsured. Today, nearly all seniors have health insurance. These programs have kept millions of Americans out of poverty and saved huge amounts in health spending.