New information technologies have resulted in a variety of new forms of communication. Among the most popular of these is hypertext (see 21.1). Landow (1992) defines hyptertext as "blocks of text and the electronic links that join them." Hypermedia, by extension, would be blocks of media and the electronic links that join them, where the "blocks of media" might be presented as still visuals or as motion visuals with Quicktime or Linkway. The term hypermedia is often (but not always) synonymous with the current use of the term multimedia. One of the more popular versions of hypertext is HyperCard, which is the popular Macintosh utility allowing students (and others) to create and use hypertext documents within a Macintosh environment. Computer programmers and others have been intrigued for perhaps a decade as to the potential of hypertext as a teaching/learning tool. Only recently have theoreticians (Landow, 1992; Ulmer, 1991; Burnett, 1993) drawn attention to the fact that the intellectual theory that undergirds the technology of hypertext is in fact postmodernism.
Ulmer (1991) suggests that Derrida's concept of graimmatology provides a useful framework for hypermedia studies. Derrida has coined the term grammatology to suggest a study or science of writing. Derrida's grammatology is grounded in the idea that writing is devalued and seen as inferior to speech. Further, written reference is unstable. This creates a "difference" such that a text must always defer to something else. To Ulmer (1991), grammatology proves a theoretic frame of reference