Abstract: In recent years, new electromagnetic surfaces like metasurfaces have continuously emerged in microwave, terahertz, and optical bands, giving rise to a field named "surface electromagnetics. " The article begins by offering an overview of surface electromagnetics, with a clear focus on defining its disciplinary scope and research framework. Based on the framework, we delve into three areas of surface electromagnetics: fundamental theory, surface design, and system applications. We believe that comprehensive research in surface electromagnetics will significantly influence and transform electronic information systems.