The two volumes of Technical Computer Science provide an accessible introduction to this important subfield of computer science. Volume 1 - Fundamentals of Digital Electronics introduces the laws of physics and electrical engineering that are essential for electronics. It then covers semiconductor devices and, building on that, electronic logic elements, switching networks, memory elements, sequential circuits, and integrated circuits. The new edition incorporates experiences from the lectures and feedback from students: terms and concepts are presented in an even more illustrative and comprehensible manner, such as the concept of voltage or the structure of bipolar and MOSFET transistors. These examples demonstrate the application of the methods introduced in the theoretical part.