In contrast, traditional approaches to interface design have taken one of following perspectives:
These four levels form a natural hierarchy, and the history of interface design has moved progressively through them. The interfaces of early computers were very close to the internal representations, using crude input devices based on binary, and professionals struggled just to get the functionality right, without too much concern for ease of use. I find it very surprising that still today, the popular media, and even many professionals, conflate user interface design with the hardware level, ignoring the issues of cognition, interaction and context that we now know are so vital to the success of systems. The second level if the hierarchy is concerned with ease of use in a purely physical sense, including issues such as the size, shape, and placement of buttons and lights; there are still professional societies devoted to this level of analysis. The third level is largely based on classical experimental psychology, and it dominated HCI (for Human Computer Interface - or Human Computer Interaction) for several decades, and is still considered basic by perhaps the majority of HCI professionals; indeed, the phrase "Human Computer Interface" reflects this bias. But there is now widespread and growing recongition of the importance of social issues for interface design, as this class discusses in detail. We consider the organizational level as part of the social level, since after all, large organizations, such as corporations and universities, are social entities.
It is notable that the history of computer science as a whole recapitulates this same hierarchy; for example, recent work in artificial life and distributed artificial intelligence is taking AI beyond the individual level into a sort of group level. Distributed computing, local networks, and the internet all mirror the same theme.
Here are some varied examples of issues relevant to interface design at the ergonomic level: wrists have 2 degrees of freedom, while elbows have 1, and the neck has 3; human color space is 3-dimensional; the QWERTY keyboard was intentionally designed to be suboptimal, in order to avoid key jams in mechanical typewriters. Though important, ergonomic issues are considered relatively routine today, and can usually be handled by straightforward experiments.
Classical HCI largely focuses on issues such as learning and error rates in using interfaces; the model for research here is experimental psychology. Although much contemporary HCI is written as if it held this rigid perspective, most of it in fact fails to fit what can be characterized as a form of reductionism (which is defined as the attempt to reduce some class of phenomena to some other class which is considered more basic). Recent work on the sociology of scientific research shows that reductionism is rarely an even approximately complete description of how science actually gets done, as somewhat discussed in Section 9 of the class notes. Contemporary cognitive psychology goes beyond this reductionist approach in several ways, as will be discussed later.
One effect of a belief in the reduction of HCI to psychology has been to raise unrealistic expectations for HCI, which then caused much subsequent disillusionment. Although this kind of boom/bust cycle is rather common in new fields, there are actually some important underlying reasons for the failure of experimental psychology to achieve everything that was expected of it in HCI, including the very significant involvement of social factors in all aspects of experimentation. Here one might mention the choice of an experimental task, which needs to be representative of tasks in the target environment for the interface, and the choice of subjects, which need to be representative of the population of real users. But social factors are far more pervasive in HCI than one might at first suppose, and go well beyond mere critiques of experimental design. The importance of social issues is particularly recognized by the newly emerging area within HCI called CSCW (for Computer Supported Cooperative Work), which is concerned with the use of computer technology by groups that are trying to work together. CSCW is discussed in some detail in Section 5 of the class notes.
It is widely recognized that many common and expensive problems with interface design, as with system design more generally, arise from an inadequate understanding of key social issues in stakeholder communities. Companies are very aware that they must take account of what their customers want, and often go to great trouble to understand the preferences of consumers. But interface designers and their managers do not seem to have learned this lesson, and often pay a rather steep price for their neglect.
In my view, the terms "user interface," "human-computer interface," and "human-computer interaction" are all rather misleading, because they exclude the larger worlds within which humans and computers live, namely the social community and the network, respectively. There is a slogan (it is the converse of one that was widely used by Sun) that
The computer is the network.but there should be another slogan that
The user is the community."Interface design" seems a better term than "human-computer interface" or "human-computer interaction," because it is more neutral about what is being mediated, though I would even more prefer something completely different that explicitly includes the social dimension. Another term, now coming into vogue, is "interaction design"; this is good but it still seems to underemphasize the social. The worst term in general use is perhaps "computer-human interface" (or "interaction"), abbreviated CHI, which is the name of the major conference in the field. Notice that choosing a good name for something is a special case of interface design!
In dealing with social issues, this course will highlight the following approaches and techniques as being especially relevant and helpful:
Narrative plays a fundamental role in many interfaces, especially (but not only) games, and narrative-like structure can be used to guide design in many other cases. Narrative is a special form of discourse, and discourse analysis considers many others, including explanations and plans. These topics are considered in href= "7.html">Section 7 of the class notes.
Metaphor will be an important topic of this course. Some notion of metaphor should be familiar from the ubiquitious "desk top metaphor" of current operating systems, such as Windows. But there are many other, and even more important, connections between metaphor and interface design; in particular, we will see that any interface can be seen as a metaphor, in the technical sense of a "semiotic morphism". Metaphor theory has been well developed in an area of cognitive science called cognitive linguistics, which is concerned with cognitive aspects of language, and this course will show how to make it mathematically precise, so that it can serve as a basis for engineering applications. We will in particular look at blending, recently postulated as a fundamental cognitive operation, and we will argue that it is just as ubiquitous in interfaces as it is in language. One of the chief proponents of blending is at UCSD, Prof. Gilles Fauconnier, in the Linguistics Dept.
Semiotics is the study of signs, and interfaces are structured signs, so if there were a fully developed "science of semiotics," it would seem to be the ideal foundation for interface design. Unfortunately, classical semiotics, as developed more than 100 years ago to study issues of meaning in logic and linguistics, is neither precise nor general enough for applications to interface design. Modern semiotics has been developed mainly for applications in the humanities - indeed, it has become perhaps the most important technical language currently used in the humanities - but it too is not precise enough for our applications, though it is widely used in critical studies of literature, cinema, photography, new media, etc. This motivates the very recent development of algebraic semiotics, as a very general but very precise theory of representation that can be used in engineering applications such computer interface design, as well as in the more traditional areas of philosophy, linguistics, and the humanities. We will have much more to say about semiotics in this course, especially in Section 4 and Section 7 of the class notes.
Ethnomethodology is a branch of sociology concerned with ordinary, real, everyday social behavior, as opposed to controlled laboratory experiments. The prefix "ethno" refers to how some group of people ("the natives") actually do something, as opposed to how some group of analysts think they ought to do it, as in ethnomusicology, ethnobotany and ethnomedicine; hence "ethnomethodology" uses the same methods of analysis that groups use in conducting their own social interactions, as opposed to the methods that some group of analysts think they ought to use. See Section 3 of the class notes for some details.
It is not difficult to justify the importance of interface design by looking at the huge effort that goes into the GUIs of current operating systems and the applications that run on them, or of major commercial websites, such as search engines, and booksellers. HCI is also recommended to be a required course in undergraduate computer science curricula by both the IEEE Computer Society and the ACM. Another way to appreciate the importance of user interface design is to consider the many examples of "high-tech" (and often highly hyped) interfaces that failed because they ignored the social contexts of their actual use, such as WebTV, Bill Gates' home music and LCD art display system, and some stockbroker support systems; we will look at some of these later in this course. Another way to appreciate the importance of this field is to look in the business section of any major newspaper, where you will see many articles on computer applications, very often focused on features of their interfaces.
Web design has become one of the major career paths for computer science students. One reason is that web design is more difficult to outsource, because interviews, testing, etc. need to be done on site. Another factor is that web technology is evolving enormously quickly, so that recent grads are in well positioned because of having been recently educated in the latest ideas, such as the rise of groupware, distributed applications, and CSCW, and the importance of understanding the sociology of users, not just their psychology and physiology. It is sobering to realize that the first proposal for the web (from Tim Berners-Lee) was only in 1989, and that by far the greatest growth has been very recent. Therefore, much of the older web authoring advice is incomplete, site specific, misleading or badly outdated, as is well illustrated by a strange piece by Karp that I found, from the early days of the web. It is also notable that it can be really a lot of work to maintain a website; this effort should not be underestimated when thinking about setting up a site (as happened to me when I undertook to provide these class notes!).
It is interesting to look at the pre-history of the web, which includes early ideas by Vanever Bush, Ted Nelson, and Douglas Engelbart. Engelbart's work is particularly important, because he had already implemented all the major features of the (so called) personal computer revolution in the mid-60s, including the mouse (on which he holds a patent), windows, menus, and remote connections. Nelson's main contribution seems to have been enthusiasm and colorful terminology, especially "hyperlink" for what we now call links; Vanever Bush had this idea much earlier. I like the term hyperchaos for what bad hyperlink design can deliver to users (see Towards a Theory of Ethical Linking, by Jeff White, for an example of this).
The fact that the web can effectively support such a wide variety of tasks is good news, but also bad news because it makes design more difficult. It is really amazing that you can find very specific facts (such as popular song lyrics), browse large areas for an overview (e.g. genetics), order any book in print, get bombarded with advertisements, meet new friends, wander at random into areas you never even knew existed, catch up on TV soap opera plots, get the latest headlines, find your homework assignments, make airline and hotel reservations, lose all your money in day trading, order a pizza, and more, all in the same medium. Solid research on web genres could be a valuable resource for designers.