A physician assistant (PA) is a licensed healthcare professional who practices medicine under the supervision of a physician. PAs are trained to perform various tasks, including taking medical histories, conducting physical exams, diagnosing illnesses, and developing treatment plans. They can also prescribe medications and assist in surgeries, depending on state regulations. PAs typically complete a master's degree from an accredited PA program, which includes both classroom instruction and clinical training. They must pass a national certification exam and obtain a state license to practice. PAs work in various settings, such as hospitals, clinics, and private practices, providing essential support to healthcare teams.