HYPERTEXT:

Multimedia can deliver the benefits of an additional interactive LEARNING LINK that sensually reinforces the usual 'boring' text or lesson. In test groups of educational applications, learning retention was improved from 30% recall to over 70% when the lesson was presented as play.

The ability to CLICK on a word in a text or an area of the image, that then CONNECTS us to another page, causing the user to experience some new, related EVENT, discovering more about the concept of the first page, constitutes PLAY for the user.

HYPERTEXT is one of the most creative basics of interactive writing. When we 'read' magazines and comics, we are decoding imagery as well as reading text at the same time. Conventional printed forms are sequential - word after word in a single-line sentence, imagery ordered to define meaning, pages numbered to control the order in which the text is read. On the other hand, dictionaries and encyclopedia require us to find a subject in an index, searching several volumes, laterally accessing information; e.g. “M is for Monkey, page 794”.

THE HYPERTEXT THEORY behind multimedia is very complex. In a hypertext document there may be no single order that determines the sequence in which to access the information. This means the user can navigate through the units in a random manner. LINKS are the fundamental unit of hypertext design. Links may be EXPLICIT (as defined by the writer, connecting an anchor node with a destination node) or IMPLICIT (not defined by the writer, but following from the various properties of the information, and selected by the user).

So, with EXPLICIT links the user can read a text about the twin carburetors of an MGB sports car. With another click, they can bring up a 3D/X-ray turntable representation of the vehicle, then pull-down a detailed plan to locate the mixture adjusting nut. The user can also hear sampled audio clips of the engine, with IMPLICIT examples of three different mixture adjustment; too rich, too lean, just right. The user can rev the car and hear how the mixtures perform.

These hypertextual links are the beating heart of interactivity and the essence of being USER-FRIENDLY.