81 Copyright © 2010, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 5 Usability Techniques for Interactive Software and Their Application in E-Commerce Shawren Singh University of South Africa, South Africa The dependability of computing is a problem with which our societies will continue to have to wrestle. Donald MacKenzie IntroductIon For a system to be usable an interface must let us- ers of the system, working in their own physical, social and cultural environments, accomplish their goals and tasks effectively and efficiently (Hackos & Redish, 1998). Meeting the needs of users who demand power without complication has made the computer in- dustry increasingly sensitive to the design of the user interface. The user interface could be the most important determinant of success for electronic commerce (Singh & Erwin, 2002). In fact, to many users, the interface is the system (Turban & Aronson, 1998). The success of any interactive product or system is ultimately dependent on it providing the right facilities for the task at hand in such a way that they can be effectively used, at an appropriate price (Dillon, 1994). To achieve success, good design is essential. In relation to E-commerce, Cockton abStract The purpose of this chapter is to provide an overview of usability and usability techniques. It discusses interaction design with a bias on web-based technologies, focusing on usability and usability defnitions. Usability principles are discussed with a particular focus on web usability, and some of the techniques that can be used to incorporate usability design and testing. The chapter also considers aspects of electronic commerce usability. These techniques are divided into usability evaluation, (heuristic evalu- ation, checklists, usability tests, think aloud approaches) followed by designing with usability in mind (including user and task analysis, walkthroughs, user experience and scenario-based usability). Several E-commerce case studies, from a developing economy perspective, are then analysed, before fnally discussing E-commerce usability. DOI: 10.4018/978-1-60566-896-3.ch005