Beijing, Nov. 8 (Xinhua, By Wang Huiwen) -- The World Digital Economy Forum opened in Beijing on November 7. The forum, themed "Digital Transformation and Sustainable Development", was sponsored by the China Association for Science and Technology (CAST), the Chinese Academy of Sciences (CAS) and the Chinese Academy of Engineering (CAE), and organized by the Service Center for Societies of CAST, and China Institute of Communication, co-organized by China Academy of Information and Communications Technology and other institutions.