To introduce blockchain technologies, including their benefits, pitfalls, and the latest applications, to the biomedical and health care domains.Biomedical and health care informatics researchers who would like to learn about blockchain technologies and their applications in the biomedical/health care domains.The covered topics include: (1) introduction to the famous Bitcoin crypto-currency and the underlying blockchain technology; (2) features of blockchain; (3) review of alternative blockchain technologies; (4) emerging nonfinancial distributed ledger technologies and applications; (5) benefits of blockchain for biomedical/health care applications when compared to traditional distributed databases; (6) overview of the latest biomedical/health care applications of blockchain technologies; and (7) discussion of the potential challenges and proposed solutions of adopting blockchain technologies in biomedical/health care domains.