This textbook covers the fundamentals and applications of sensor systems, with a focus on sensor systems fundamentals. It provides an in-depth explanation of the physics and operation of various sensors, including multidimensional sensor networks and multisensor data fusion. In addition to selection and performance specifications, it also discusses the required hardware and software for integration within technical systems. Furthermore, signal processing, data analysis, parameter determination, and decision-making are treated extensively. The book combines the insights of a standard course textbook with practical information for application in engineering and system development.