Technical systems with ¿interacting surfaces in relative motion¿ especially in mechanical engineering, production, and transport; including the analysis of friction-induced energy losses and wear-induced materials dissipation. Technical systems that require a combination of mechanics, electronics, controls, and computer engineering for needs of industry and society. Technical systems with a combination of mechatronics and internet communication. Cyber-physical Systems for the digitalization of Industry in the development project Industry 4.0. Considers technology as combination of the physical world and the digital virtual world of information and communication. Describes the product cycle of technical systems and the corner stones of technology: material, energy and information. Presents a holistic view of technology and engineering.