A few practical remarks on the user-friendliness of online systems
A list of general properties of a user-friendly online sys tem is presented. Unfortunately, the requirements of experi enced users on the one hand, and of the beginners or inci dental users on the other hand, are contradictory. Synonymous commands, less strictly formalized input data transformed to standardized formats by intelligent input programs, explicit as well as implicit input data, free choice between default or user's own parameters and procedures or macrocommands, can make any system more friendly even for heterogeneous user population. Similarly, flexibility of output (e.g. elo quent natural-language messages for non-experienced users and concise coded and abbreviated output for experts) im proves acceptance of the system by all users. Examples of flexible, free forms of commands, input and output data are given.