ABSTRACT
Two types of standards are distinguished in user interface technology: standard user interfaces and standards for user interfaces [Stewart 1990]. The first type establishes a de facto standard for user interface implementation, either provided as a corporate standard by a leading software producer (e.g., OPEN LOOK [Sun 1990] and Windows [Microsoft 1994]) or defined by consensus within the software industry (see OSF/Motif [OSF 1994; Berlage 1995]). The second type comprises a series of standards [ISO 9241 1999, Part 10 through Part 17] that are devoted to dialogue techniques of interactive systems, such as menu dialogues or direct manipulation. These standards provide design recommendations but do not include any guidance for implementation, nor do they involve toolboxes or programming interfaces. In addition to the product design standards, a process standard has been published [ISO 13407 1999] providing recommendations for user-centered design processes, such as context and requirements analyses. Meanwhile, usability engineering has been established as a discipline on its own right, like software engineering [Mayhew, 1999; Rosson and Carroll, 2002]. Both disciplines will set their own standards, as is typical with traditional engineering disciplines (e.g., civil engineering). Hence, the previously mentioned standards for designing products and processes can be called usability standards or usability engineering standards.
