Conclusion

Write hypertext linking to other documents. Now, you get

Online help on all systems
Editing in markup, (or wysiwyg on NeXT)
Network access
Browsing with DynaText (?)
Generation of ASCII text (PS, RTF on NeXT)

Later, you get

Full text indexing for initial query
Pretty document generation
Fancy browsers on more platforms (X)
Links to more and more data on the net

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