Usability

The processes and methods of Usability existed prior to the more recent popularization of User Experience concepts. In the beginning, the issues of usability were more concentrated in the developing areas of scientific and business computing, aerospace, and military technologies. Most programs, systems, or technologies were developed to be implemented by a "user" that usually did not have an understanding of the complexities of the system beyond the "interface" with which they interacted. It became apparent to system developers, over a period of time, that it would be helpful to really understand what the user needed and how the user perceived their experience of the technology. Usability Engineering methodological approaches "have been evolving since the 1970s [and] is a discipline with roots in several other basic disciplines, including cognitive psychology, experimental psychology, ethnography, and software engineering." (Mayhew, 1999).

According to usability expert, Jakob Nielson, "any object, product, system, or service that will be used by humans has the potential for usability problems and should be subjected to some form of usability engineering." (Nielson, 1993). According to Nielson, "'It's all explained in the manual' should never be the system designer's excuse when users complain that an interface is too difficult." (Nielson, 1993). The value of effectively communicating with the user is especially important in systems or technologies that are life-critical, such as a weapons guidance system, or an x-ray machine for medical imaging. In these cases user error could potentially cause great harm.

According to Deborah J. Mayhew, in the development of software systems, there are three stages of the Usability lifecycle: 1) Requirements Analysis, 2) Design/Testing/Development, and 3) Installation. (Mayhew, 1999). The first step in the Usability process is Requirements Analysis, and the focus is researching the user, and their processes and goals in order to create an application that addresses these concerns. This process can include informal or formal interviews, the development of user profiles and use case scenarios. The requirements may also include technical specifications for the context of the system or product. This research occurs prior to the development phase. After the release of the product or service, follow-up research is conducted to assess the success or failure in the attempt to meet the user's needs. The second phase in the Usability process concentrates on Design, Testing and Development. Given the results of the research, the context of the product or service, and the resources available, a design timetable is initiated at this stage. There are many ways that a product or service can be developed - but prior to the production phase the initial concepts must be decided, which usually involves the creation of prototypes and testing in an iterative process. Design prototypes may be low-fidelity, such as those printed on paper, or high-fidelity, such as clickable, dynamic models. (Mayhew, 1999). Testing processes can be informal or formal, conducted with one or many users, done remotely or in a usability lab specifically designed for that purpose. There are many guidelines concerning the development and enactment of design and testing - which vary greatly depending on the product and the users. The development phase proceeds as the design and testing issues are sorted through and resolved. It is possible to have some features of the project in development while others are still in the design or testing stages. Installation is the final step in the process, and includes follow-up with the user, maintenance, and product updates. •