Getting the picture

When designed well, user guides and related documentation can reduce significantly the costs of manufacturing, operating and maintaining products. Diagrams can be key features of such informational material, but, until recently, they have not been the subject of serious study. Diagrams are powerful information resources: this power arises from the use of graphic metaphor, which can also cause problems of interpretation. A taxonomy is presented of the fundamental design variables available when creating diagrams. User guides, and the diagrams they contain, are integral to products, and their development is the business of information designers. The scope of information design has been extended enormously now that diagrams may be animated, interactive and distributed digitally around the globe. The multimedia technical documentation system developed at Coventry University, called the 'cinegram', is outlined, and the re-utilisation of three-dimensional CAD data for instructional purposes at Rolls-Royce Aerospace is described. Future research is signalled, including the possibilities for hybrid 2-D and 3-D interactive diagrammatic documents.