Brown, P.J., Turning Ideas into Projects: The Guide System. in Proceedings of the ACM Conference of Hypertext, (Chapel Hill, North Carolina, 1987), ACM, New York, NY, 1987, 33-40.

"Guide is aimed at naive users, both authors and end-users, as any product aimed at a mass market must be. The number of systems that claim to be suitable for naive users is probably ten times greater than the number that really are. However Guide can point to some success in this area, and I shall now outline the design principles that led to this. [...]

"The most important mechanism in Guide for exploring documents is the replacement-button. The replacement-button is a button within the document. [...]. When selected with the mouse, a Guide button is replaced in-line by the material linked with that button [...]. Typically the author will present a document initially in summary for, with replacement-buttons to allow the user to expand the parts of the document that interest him. [...]

"Typically the replacement of a button itself contains further buttons. A reader explores a document by successively expanding buttons, until he reaches the level of detail he wants. He thus tailors the document on the screen to his reading needs. Sometimes the reader will wish to go back to a lesser level of detail. He can at any time 'undo' the replacement of any button previously selected, thus folding the replacement back under its original button. This saves screen space and generally makes the document more manageable and understandable. As the user sees it, this folding mechanism is particularly simple: if anything you see is at too great a level of detail you just point at it and click the mouse-button; the offending material is then folded back under a button." (35-36)

If a Guide user needed to have to learn more than (say) five facilities before using it, then most users would give up. Guide end-users onlyneed to master four facilities (though, to be exact, there is a bit of play in this figure since it depends on what you count). These are:

- travelling round the document using the scroll-bar. (On the Macintosh this mechanism will already be familiar to most users.)

-replacement-buttons.

-note-buttons (or glossary-buttons in UNIX Guide).

-reference-buttons. (37)