Synergy and Subsidiarity: The Systematic Determination of Software,User, and Operating Instructions

The quality of a software product is determined by its usability; the quality of technical documentation is determined by its comprehensibility. Usability conceptualizes the person using a software product to perform a task; comprehensibility deals with the reader of operating instructions-although they are generally one and the same person. However, only rarely are the software and technical documentation part of an integrated design.

This is all the more surprising in that, on the technical level, the boundary between software and user information is becoming increasingly blurred; one need only think of the hypertext links between software and help systems, or of electronic versions of operating instructions.

We make the case for considering user, software, and operating instructions as a single system oriented toward performing a task; the operating instructions therefore are regarded as a subsidiary subsystem of a structure to be described. This is done from a linguistic perspective, with reference to the central category of knowledge available to the user or contained in the software and in the operating instructions and that we approach via an empirical analysis of authentic material (operating instructions as primary data, statements of end users concerning operating instructions).

Taking the example of creating software and operating instructions for a computer tomograph, we show how the relevant knowledge elements contribute to the accomplishment of an operating task and discuss the resultant requirements concerning the contents of software and operating instructions, particularly for handling fault and problem situations.