There are many differences between Medicare and Medicaid. The simplest way to differentiate between the two is that Medicare is earned by working, while Medicaid is given to those who qualify for it. Most people generally qualify for Medicare once they are 65 or older, have resided in the U.S. for a minimum of five years, are a U.S. citizen or legal resident, and, most importantly, have worked at least 10 years in Medicare-covered employment. While, Medicaid is based on needs and the inability to afford treatment. A person may have both Medicare and Medicaid. This occurs when a person has worked and met the requirements for Medicare and due to their current needs they qualify for Medicaid as well.