[*] We would like to draw a distinction
between virtual documents and the technologies used to achieve the effect of
virtual documents. One can use CGI, HTML, downloadable applets, and mediating
proxies to generate presentations on the fly. However, these technologies do
not inherently produce results that look and feel like documents, are
generative (e.g., constructed or composed from parts), and change content in
response to reader input. These are the salient properties of virtual
documents, however they are implemented.