For approximately 10 years, superconducting quantum circuits printed on silicon chips are used to study the fundamental laws of quantum mechanics. Two prototypical examples for such circuits are transmission line resonators (boxes or memories for quantum light) and quantum two level systems (qubits). From a scientific point of view, superconducting quantum circuits allow for the investigation of fundamental quantum mechanical effects such as light-matter interaction. In addition, they are one of the most promising platforms for quantum computing, quantum communication, and quantum sensing. In these areas, superconducting quantum circuits are explored in industrial research and development worldwide.