INVARIANT USER INTERFACES
Abstract
In this article the term invariant user interface is introduced for a generic, stable backbone of all user interfaces, which contain a set of predefined elements and rules to build complex interactive systems. Invariant user interfaces specify fix points in using information systems. We argue that in interfaces of complex software applications such fix points are increasingly necessary. Based upon psychological assumptions and results of human computer interaction (HCI) studies, the necessity and benefits of invariance is shown, among others increased efficiency, enhanced reliability of use and decreased cost of software ownership. In this article invariance properties of state-of-the-art user interfaces are summarized, and a simple interaction model is introduced. Types and limits of invariance is defined using this model, and a set of fundamental criteria is characterized that invariant interfaces must meet.