Simplicity, Consistency, Universality, Flexibility and Familiarity: The SCUFF Principles for Developing User Interfaces for Ambient Computer Systems

2. User Interface Design Guidelines And Principles

The process of user interface design can be highly complex, as typically there are many competing variables involved. We could describe those variables as the who (the user population), the where (the environment the proposed system will be used in), the how (the style of user interaction, and the design of the tasks), and the what (the technological nature of the devices as well as the software/hardware constraints). Most user interface designers champion the who as the most important of the four variables, and consequently advocate a user-centred approach to their work.

To support designers in their consideration of users, a number of guidelines have been published over many years. Such guidelines aim to steer designers by keeping them on the track of developing quality, consistent user interfaces that conform to the standards expected by the owners of the guidelines. Examples of these include Apple’s I-phone Human Interface Guidelines (Apple Inc., 2010) and Microsoft’s Inductive User Interface Guidelines (Microsoft Corporation, 2001). As they tend to be for specific styles of interaction, for known types of devices, and for tasks that take place in typical environments (in other words the how’s, what’s and where’s are predictable), such guidelines are always highly detailed.