The Health Insurance Portability and Accountability Act of 1996 (HIPAA) is a law intended to make it easier for people to keep their health insurance when they change jobs. The law set standards for the electronic exchange of patient information, including protecting the privacy of such records. The U.S. Department of Health and Human Services issued a Privacy Rule to implement that aspect of the law, and its Office of Civil Rights is in charge of enforcing it. Essentially, HIPAA requires covered entities to keep private protected health information, or PHI.
For more information on HIPAA, see this AHCJ tipsheet.