ABSTRACT
The Human Factors approach is to position the human at the centre of all activities and to consider the human system and interactions from this perspective. An example of a simple model that portrays this is the SHEL concept (Edwards, 1972; Hawkins, 1984). The SHEL concept was named after its components: software, hardware, environment and liveware. The latter, liveware, represented the human. There have been a number of pictorial representations of the SHEL concept as ideas concerning the system resources have been refined. An example of one diagrammatic representation of the model is to place L (for liveware) in the centre of a square surrounded by four other squares (S, H, E, and L) in a symmetrical cross shape. This is shown in Figure 2.1.
