二十一世纪是知识经济时代,是信息高速发展的时代。农业经济时代是以土地为资源,工业经济时代是以原材料为资源,而知识经济时代则是以信息为资源。为抢占新世纪经济制高点,世界各国都不约而同地全力推进社会信息化建设。信息以通信网络为载体,以数字技术为手段,网络化、城市数 The 21st century is an era of knowledge economy and an era of rapid development of information. Agricultural economy is based on the land as a resource, the industrial economy is based on raw materials for resources, and knowledge-based economy is based on information as a resource. In order to seize the commanding height of the economy in the new century, all countries in the world are making every effort to promote the construction of social information. Information to the communications network as a carrier, digital technology as a means of networking, the number of cities