Vannevar Bush is often credited with describing the first hypermedia
system, named memex.  He wrote about it in his 1945 article _As We May
Think_.  There is an HTML versions at <URL:http://www.theatlantic.com/
unbound/flashbks/computer/bushf.htm>.  Paul Otlet has also been credited
with the development of what we now think of as hypertext, in 1934.  See
<URL:http://alexia.lis.uiuc.edu/~wrayward/otlet/xanadu.htm> for a version
of an article from the Journal of the American Society for Information
Science v.45 pp.235-250 for more details. 
  Ted Nelson coined the terms hypertext and hypermedia to describe his
proposed system called Xanadu.  According to an article in Vassar College's
Miscellany News, he used the term hypertext in a talk there in 1965
<URL:http://iberia.vassar.edu/~mijoyce/Ted_sed.html>.  The Xanadu homepage
is at <URL:http://www.xanadu.com.au/xanadu/>.  His book _Literary Machines_
is largely about Xanadu.  Douglas Engelbart demonstrated the first
computerized hypertext system, called NLS/Augment circa 1968.  He also
invented the computer mouse, graphical user interface, etc.!  For more
information about Englebart and his projects see the Bootstrap Alliance
homepage at <URL:http://www.bootstrap.org/>.  Randy Trigg wrote the first
Ph.D. dissertation based on hypertext circa 1986.  The first hypertext
conference was held in 1987.  The alt.hypertext newsgroup was created in
1992.

  _Memex and Beyond_ is a major research, educational, and collaborative
web site integrating the historical record of and current research in
hypermedia: <URL:http://www.cs.brown.edu/memex/>.

  Jorn Barger's hypertext timeline is at <URL:http://www.robotwisdom.com/
web/timeline.html>.