The World Wide Web, however, has several limitations. It provides no means other than hyperlinks for structuring information, and these links are one-way, making it impossible to find out which links refer to a particular document. Although W3 supports multimedia, links can be embedded only into text documents. Also, it has no search facilities of its own and relies on external search engines, such as WAIS, for this purpose. Though the CGI interface lends flexibility to W3 servers, this flexibility comes at a cost.
Different servers behave differently and the uniformity of the interface is lost.
The Web also provides little support for the maintenance of large datasets, sometimes making it necessary to have several W3 servers within a single organisation. The three systems described above are part of the first generation of Internet information systems. They work well in certain contexts but all have their limitations when applied in particular situations. Hyper-G was designed to overcome these limitations.