An exact widely accepted definition of “web usability” is extremely difficult to provide as it greatly depends on the viewpoint of those undertaking the study. Some researchers examine usability from the perspective of pure design, others from technical elegance and performance when it is evident that a only a properly selected mix of these can provide a usability result that is meaningful. I have developed the following questionnaire to discover how usable a website is based on five major criteria:
- Design. Hassan & Li (2001) and Nielsen (2003) agree that the user experience in usability is greatly affected by the site’s pleasing look and feel, which is an unquantifiable criteria as the outcome is a personal opinion of the user, however, when quantified by Cappel & Zhenyu (2007), all three researchers agree that navigation and interactivity should be clear. This can be quantified by how quickly a user can learn to navigate the site and accomplish tasks and to understand links and where they are and where they have already visited.
- Content. Hassan & Li (2001) argue that this is extremely important in establishing trust with the user and should be aimed at the target audience and phrased accordingly. It may therefore also be important that those will disabilities (e.g. using screen readers or no images) can still use the site (accessibility in its strictest sense). This can be verified by online validators such as Access Keys (2010), for colour contrast, and AChecker (2010) for accessibility features.
- Accessibility. In addition to the accessibility mentioned in “Content” above, Hassan & Li (2001) suggest that accessibility extends to the ability for the user to access the site in terms of availability, performance and compatibility with a range of web browsers. Standardisation and page load has a great effect on performance, availability and compatibility which can be checked using WebOptimization.com (2010) and W3C (2010).
- Errors. Nielsen (2003) suggests that this is an important factor in web site usability in that a user should be able to easily recover from any errors they make.
- Search-ability. Cappel & Zhenyu (2007) found in their study that the ability of the user to search rather than hypertext link was extremely important to usability, especially on content heavy sites, therefore this should be included to render the site usable.
Access Keys (2010) Access Color: Color Contrast Tool [Online]. Available at http://www.accesskeys.org/tools/color-contrast.html (Accessed 20 Mar 2011).
AChecker (2010) Web Site Accessibility Checker [Online]. Available at http://www.atutor.ca/achecker/ (Accessed 20 Mar 2011).
Cappel, J & Zhenyu, H (2007) ‘A USABILITY ANALYSIS OF COMPANY WEBSITES’, Journal of Computer Information Systems, 48, 1, pp. 117-123, Business Source Premier, EBSCOhost, viewed 20 March 2011.
Hassan, S & Li, F (2001) Identifying Web Usability Criteria [Online]. Available at http://aim.johnkeston.com/im2420/wp0103.pdf (Accessed 20 Mar 2011).
Nielsen, J (2003) “Usability 101: Introduction to Usability.” [Online]. Available at http://www.useit.com/alertbox/20030825.html (Accessed 20 Mar 2011).
W3C (2010) Markup Validation Service [Online]. Available at http://validator.w3.org (Accessed 20 Mar 2011).
WebOptimization.com (2010) Web Page Analyzer [Online]. Available at http://www.websiteoptimization.com/services/analyze/ (Accessed 20 Mar 2011).