ABSTRACT
Icons are the special graphic devices, typically non-alphabetic or nonnumerical, that have been an important feature of user interfaces since the introduction of the rst WIMP systems for the Xerox Alto in 1972 and Star in 1981. In other contexts they are usually called pictograms, symbols or graphical symbols. Although icon e€cacy in user interfaces was not tested before introduction (Bewley et al. 1983), developers of the Alto and Star wrote, ‘Our intention and hope is that users will intuit things to do with icons, and that those things will indeed be part of the system’ (Smith et al. 1982).
