by Adrian Miles 
InterMedia UiB and RMIT 

Currents in Electronic Literacy Spring 2001 (4), <http://www.cwrl.utexas.edu/ 

Usability is the most recent term for the general consideration of navigation and readability in hypertext. The assumption that readers would be lost in a hypertext is a problem that has haunted hypertext virtually from its inception. Research in this area has, interestingly, concentrated on the link as a fundamental unit of hypertext structure and as the point at which usability becomes problematic, the moment of enabling risk.

For instance, George Landow in his landmark essay, "The Rhetoric of Hypermedia," argues forcefully for clarity and intelligibility around link sources and destinations, and under the heading "The rhetoric of departure" argues "[r]eaders of hypermedia need some indication of where they can find links and then, after they have these indications, where those links will lead them and why they are led there" (96). Additionally, in a subsection entitled "The rhetoric of arrival (graphic documents)," Landow details the following rule:

Rule 17. Texts serve not only to provide information but also to reassure the reader that the link embodies a significant relationship and to provide some hint, however incomplete, of how that relationship can be formulated by the reader. (99.)

Indeed, Nielsen more recently explicitly adopts Landow's terminology and rhetoric when he argues that:

A hypertext link fundamentally has two ends: the departure pages and the destination page. Links should follow two principles to increase their usability relative to their two ends:

The rhetoric of departure. Clearly explain to users why they should leave their current context and what value they will get at the other end of the link.

The rhetoric of arrival. Clearly have the arrival page situate users in a new context and provide them with value relative to their point of origin. (Nielsen 66.)

While these guidelines appear to rely on common sense, it is equally apparent that link use when considered in terms of usability is in fact strongly tied to the general problem of accessibility and architecture, and is not a problem of hypertext rhetoric per se. Indeed, it seems clear that the language used to describe hypertext structure by Nielsen, Landow, and others reflects an anxiety around the link, an anxiety that adopts the language of a rational and ultimately realist aesthetic.