Implanted biomedical devices are becoming ubiquitous in the practice of medicine but are at risk for biofilm-related infection. The biomaterial composition of these devices can significantly affect their risk for infection. Biomaterials design is complex with compositional choices leading to different properties, including mechanical strength, biodegradation rate, and ability to locally release therapeutics. In this review, we introduce the field of "Implant Infectious Diseases," review practical biomaterial fundamentals for the infectious disease clinician, and apply these principles to case vignettes. This review serves as a primer for a broad infectious disease audience to better understand the role of biomaterials in medical devices and as therapeutics.