Building a User-Defined Interface

A measurably easy-to-use interface has been built using a novel technique. Novices attempted an electronic mail task using a command-line interface containing no help, no menus, no documentation, and no instruction. A hidden operator intercepted commands when necessary, creating the illusion of a true interactive session. The software was repeatedly revised to recognize users' new commands; in essence, the users defined the interface. This procedure was used on 67 subjects. The first version of the software could recognize only 7% of all the subjects' spontaneously generated commands; the final version could recognize 76% of those commands. This experience contradicts the idea that people are not good at designing their own command languages. Through careful observation and analysis of user behavior, a mail interface unusable by novices evolved into one that let novices do useful work within minutes.

Wixon, Dennis, John Whiteside, Michael Good and Sandra Jones. ACM SIGCHI (1983). Design>User Centered Design>User Interface