The Beidou navigation satellite system (BDS), one of China's three most famous trademarks, has become another Chinese business card that has entered the international arena after high-speed railway and nuclear power. It is a major achievement of scientific and technological development and innovation since the country started reform and opening up.This is an authoritative book that comprehensively, systematically and scientifically introduces the BDS and its application, with the aim to let the international community better understand China's technological innovation capability and achievements embodied in the system, and to provide the world with authoritative answers to the questions or doubts about BDS.