From the perspective of Internet of Things (IoT) applications, this book first describes the basic concepts, architecture, key technologies, standardization system, IoT+ and other knowledge of IoT, and then focuses on the engineering development of IoT (main control layer, sensor layer, wireless transmission layer RFID, NFC, LoRa, NB-IoT, WiFi, ZigBee and Bluetooth), and practical cases of IoT applications. Supplemented by corresponding IoT hardware development environment, and hardware development modules, it strives to let readers have a comprehensive scientific grasp of the future applications and development prospects of Internet of Things from the forefront of science, cultivate future-oriented thinking mode of IoT and the ability to develop and practice IoT, as well as improve the capability to apply IoT to solve practical problems.