OPC stands for openness, productivity, and collaboration, symbolizing the powerful and modern connection of automation components with control hardware and field devices through a standardized, manufacturer-independent access method. The new OPC generation, Unified Architecture (UA), aims for global interoperability and defines a service-oriented, manufacturer-independent, and cross-platform data and information exchange—from field devices at the factory level to ERP systems at the corporate management level. This book covers the emergence, objectives, and fundamentals of OPC and OPC UA, presents existing and emerging specifications, as well as Companion Standards such as FDI (EDD, FDT), ADI, or IEC 61131-3/OPC UA, and discusses the approach to designing and implementing components as well as development.