TRICARE Online is a web site of the Military Health System. The Office of the Assistant Secretary of Defense, Health Affairs and the TRICARE Management Activity provides it as a public service. TRICARE Online may be used to make medical appointments, review medical claims, order prescription renewals or refills, and make enrollment changes. The system may also permit users to communicate electronically with health care providers, create or customize a TRICARE Online web page, and use the Personal Health Care Manager.