What is Web Usability

In this chapter the author analyzes, from a cognitive pragmatics point of view and, more specifically, from a relevance-theoretic approach, the way Internet users assess the qualities of web pages in their search for optimally relevant interpretive outcomes. The relevance of a web page is measured as a balance between the interest that information provides (the so-called “positive cognitive effects” in relevance theory terminology) and the mental effort involved in their extraction. On paper, optimal relevance is achieved when the interest is high and the effort involved is low. However, as the relevance grid in this chapter shows, there are many possible combinations when measuring the relevance of content on web pages. The author also addresses how the quality and design of web pages may influence the way balances of interest (cognitive effects) and mental effort are assessed by users when processing the information contained on the web page. The analysis yields interesting implications on how web pages should be designed and on web usability in general.