By the end of June, 2020, fifty-five BeiDou satellites (send) up, meaning the completion of China's self-developed BeiDou Navigation（导航）Satellite System (BDS). BDS appears later than America's GPS, Russia's GLONASS and EU's Galileo, it can equal them. As one of the four global navigation satellite systems, BDS involves（combine） efforts of over 400 agencies and 300, 000 research personnel and technicians.
Originally drafted in the 1980s, the project represents a milestone(里程碑) in China's space effort. BDS is comparable to GPS in terms of the (accurate) of positioning and it has been applied shared bikes in Daqing. It also offers short message communication, provides emergency communications in areas that fail to pick up clear conventional communication signals occasionally. In effort to improve the quality of some positioning (serve), Apple and Samsung phones, among others, are already using BDS' signals, and so is every Chinese brand.
The construction of complete BDS is a huge technical achievement for China and can (true) pay off in the near future. Meanwhile, (promote) the world's economic and social development as well as peaceful use of space with BDS's remarkable contribution has attracted the world's attention.
