WWW is an information retrieval service tool based on hypertext. This hypertext way of organizing the world's information does not adopt the top-down tree structure, nor does it follow the cataloging structure in the management of books and materials, but adopts the super-mesh structure of pointer link. Hypertext structure can link information anywhere through pointer connection, which can be direct or indirect, unidirectional or bidirectional. Therefore, when retrieving data, it is very flexible, and you can jump from one information resource to another local or remote information resource through the pointer. Moreover, the reorganization of information is also very convenient, including adding data at will or deleting and merging existing data.