In view of the theme of the World Meteorological Day in 2022, this paper reviews the understanding process of the importance of meteorological and hydrological information in the development of atmospheric science, as well as the cooperation experience and results of the international community in the field of meteorological observation and data exchange, especially the achievements and challenges since the establishment of the World Meteorological Organization （WMO）. Finally, the latest achievements of WMO reform in the field of information policy are introduced.