Book excerpt: Gas Sensors Based on Conducting Metal Oxides: Basic Understanding, Technology and Applications focuses on two distinct types of gas sensors based on conducting metal oxides. Ion conduction, applied in so-called solid-state electrolytic sensors for one, and electronic conduction used in semiconductivity gas sensors for the other. The well-known ?–probe, a key component to optimize combustion in car engines, is an example of the former type, and the in-cabin car air-quality control SnO2 and WO2 sensor array stands for the semiconductivity type. Chapters cover basic aspects of functioning principles and describe the technologies and challenges of present and future sensors. - Provides reader background and context on sensors, principles, fabrication and applications - Includes chapters on specific technological applications, such as exhaust sensors, environmental sensors, explosive gases alarms and more - Presents a structured presentation that allows for quick reference of vital information