2.4. Human-Computer Interaction

Research in HCI set out to define basic terms in the field and to further develop an understanding of the nature of the interaction between humans and computers. It concerns both the human user and the computer system with the aim to make the interaction between the two easier and more satisfying. HCI is the effort of bringing together two non-trivial systems for optimisation is a highly complex task: computers as highly complex machines and humans as highly complex organisms.

At the same time HCI has to ensure good integration into the organisational settings in which they are to be used (user acceptance, proper tasks and functionality mappings). Shneiderman (1998) stated that proper HCI is important in terms of

§         Business: Quick Success Stories and Miserable Failures - Systems with user-friendly interfaces, proper functionality and appealing design are more quickly accepted than less well designed ones;

§         Competition: Everyone is thriving to attract more customers/users by having friendlier and more appealing interfaces, thus creating very intense competition (e.g. browsers,  mobile phones, PDAs);

§         Productivity: Reduce costs or training and time to complete tasks;

§         Increased safety: Reduce human-related errors.

 

Three dimensions of HCI

To achieve better user interfaces we have to understand three dimensions: (a) how users function, (b) the task they need to perform, and (c) how computer systems can be structured to facilitate the ease to carry out the desired task (Faulkner, 1998). The different dimensions are elaborated in more detail in the following list and their relationship is visualised in Figure 5.

  • The system-level/macro-level: Communication theory, aspects of psychology and sociology have to be considered to understand what and how people (re-)act. The setting in which the user performs must be taken in account: as humans are social beings, no user acts isolated, nor is any task. Thus the relations to other tasks have to be considered. Acting will effect people - a socio-technical designs is required! [1]

  • The task-level/micro-level: Concentrating around the user and his task, the main question on this level is, what actual problem the user wants to solve and what abilities are involved. It considers memory, vision, cognition, mental and motor skills. Additionally the nature of the task has to be considered. This level demands for a user-centred design.

  • Usability design: The main question when accomplishing the task is what the system can do for and how it might best communicate with him. An additional difficulty is that any user interface has to serve many users, all are individuals with different backgrounds, problems and abilities. Different to the others, the dimension of usability cannot be clearly separated from other issues: it is an integral concern during the product life cycle and its stages. It uses findings from other disciplines but is a field in its own right.

Remark: To point out the development towards computer centred appliances the formerly used term Man-Machine-Interaction was gradually replaced by HCI throughout the years.

Computer Mediated Communication

A subcategory to human-computer interaction with a different role of the computer is Computer Mediated Communication (CMC). Computer Mediated Communication describes the ways humans use computer systems and associated networks to transfer, store, and retrieve information related to a communication process. In this context computers are considered as mediators for communication rather than processors of information. CMC can provide communication access to persons, resources, and information, independent of time and distance. Santoro (1995) suggests: "CMC refers to computer applications for direct human-to-human communication". Applications are e.g. learning tools in the field of computed mediated education, where the computer is a resource to help students construct their own knowledge. HCI as the more general concept includes techniques used in CMC, therefore we will investigate more into HCI even if the applications may be in the area of CMC.

 

[1] Foundations of psychology for HCI are discussed in detail in Card et al. (1983), communication theory in Littlejohn (1996) and Griffin (2002), and helpful aspects of interpersonal psychology and sociology in Fiske (2004).