History of Hypermedia
Hypertext | Hypertext Systems | Hypermedia

Hypertext is the term used to describe systems which allow highly interactive electronic documents to be created and published. The main distinguishing feature of hypertext documents is that they are nonlinear.

They allow links between parts of documents for purposes such as explanation and expansion, comment or criticism.

Hypertext documents overcome the physical constraints of paper in that they do not have to present information in a sequential fashion. The reader is not left with the task of physically finding and obtaining separate sections or volumes. In contrast hypertext systems allow authors to create electronic paths through related material, to cross reference other documents, to annotate text and to create notes.

Hypertext - Origins

The mechanization of documentation, particularly of technical information, was a particular interest to Vannevar Bush, who in 1930 had built, along with colleagues at the Massachusetts Institute of Technology, a general purpose differential analyzer - regarded by many as the first electronic computer.

In 1941, Bush was appointed the first director of the United States Office of Scientific Research and Development. In this role he was responsible for some 6,000 scientists engaged in defense research during the Second World War. In 1945 he wrote an article called "As We May Think", which was published in the July edition of Atlantic Monthly in which he stated:

"The summation of human experience is being expanded at a prodigious rate, and the means we use for threading through the consequent maze to the momentarily important item is the same as that used in the days of square rigged ships ... our methods of transmitting and reviewing the results of research are generations old and by now are totally inadequate in their purposes."

Non-Linear Literature

Users of hypertext systems can quickly follow references and footnotes, or see figures and charts, without losing their original context. Although it sounds as if this is a technology to be applied only to dry, technical documentation, its scope is much, much wider than that.

Ted Nelson, who coined the phrase Hypertext, published a book titled Literary Machines and described hypertext as a fundamental approach to the management of literature which at its heart has a technology which will ultimately lead to it becoming ubiquitous.

In another of his books, Dream Machines, (1965) Nelson wrote:

"By 'hypertext' I mean nonsequential writing. Ordinary writing is sequential for two reasons. First, it grew out of speech ... which (has) to be sequential, and second, because books are not convenient to read except in a sequence. But the structures of ideas are not sequential. They tie together every which way. And when we write we are always trying to tie things together in nonsequential ways."

A New Technology

According to Nelson, hypertext technology represents a breakthrough in information technology with repercussions every bit as powerful as the invention of the printing press, movable type or telephones.

Ted Nelson coined the term hypertext in 1963 and fully expected it to catch on like wildfire. It did - but not until 1986. The reasons for the delay are straightforward; only relatively recently has it become possible to efficiently store and display high quality documents on relatively low cost personal computers.

The challenge now arises to define the grammar of this new form of literacy - to provide a new type of document which, in addition to normal features, can also interact with its reader - and to exploit the resulting possibilities to the full.