Dr. Farzad Mostashari, the former National Coordinator for Health Information Technology at the U.S. Department of Health and Human Services, is a top source of information on health care and health-related technology. For a topic that can quickly get confusing, Dr. Mostashari offers lighthearted, but direct commentary. He wears great bow ties, too. (In fact, his bow tie has its own Twitter handle.) —Alexandra Sifferlin