One person, one computer. ?span>Apple Computer slogan Imagine that you have just boarded an airliner resplendent in its livery: fitted with a wide choice of video and audio for every glove-soft, leather-covered, oversized seat; its galleys provisioned with fine food and drink. You take your seat and look out the freshly cleaned large window. With a sigh of anticipation for a particularly pleasant flight, you reach into a small compartment in front of you to see what is there. A not-too-small bottle of your favorite beverage comes to hand first, followed by a little booklet about this remarkable airliner. As the flight attendants swing the doors shut and you settle in, you read the booklet. You learn that the aircraft is the work of some of the finest interior designers from all over the world, that chefs from five-star restaurants have created the menu and personally prepared the dishes, and that because the internationally acclaimed artists who designed the exterior made the craft look so much faster than any other airliner, there had been no need to include professional aeronautical engineers in the aircraft's development team. In the small print used for legalese, the booklet warns that the ride tends to be bumpy, even in the absence of turbulence, and that the plane crashes regularly. However, the booklet promises, until any of those events occur, you will be comfortable and well entertained. Suddenly, the latching of the doors seems menacing instead of promising. Your equanimity is gone; you are trapped. This flight, the only one to your destination, is doomed, and you are on it. At this point, you'd rather be sitting on a hard seat, no drink in your hand and no window by your side but in an aircraft blessed by great engineering. This absurd situation closely parallels the nature of most human-machine interfaces today. Our computers and cellular telephones have the latest chips and electronics; today's operating systems are a feast for the eyes, with glorious colorful backgrounds and three-dimensional tromp l'oeil effects. You click on a button, and lo! it appears to move most realistically; you hear a digital stereophonic, full-fidelity rendering of a switch clicking, and your ears are enchanted by a resonant harp glissando as a window opens before you. But when you start to use the system, it begins to poke you with uncomfortable corners of unexpected behavior. You cannot find the command you want among the thousands that the system provides. Simple, routine tasks take forever to do. The program you bought last year does not run under the improved operating system, so you have to buy an upgrade. And, of course, the system crashes regularly. Some engineering fundamentals that are not widely known underlie good interfaces. And why should those fundamentals be studied? How interfaces should look and work seems well established: They've been incrementally improved for two decades now; we have interface guidelines published by the major software producers to ensure future compliance; development tools allow us to put together interfaces quickly such that they look just like other modern interfaces just as my mythical airliner looked just like a well-designed, safe, and comfortable flying machine. But consider what these interfaces fail to do for us. When you want to set down an idea, you should be able to go to your computer or information appliance and just start typing: no booting, no opening the word processor, no file names, no operating system. (My definition of an operating system: What you have to hassle with before you get to hassle with the application.) You should not have to learn an entire new application to perform what you know to be only a few simple tasks that you'd like to add to the repertory of your system. Regrettably, the design of interfaces has taken a wrong turn, leading to a level of difficulty unjustified by technological or logical necessity. Millions of us have a love-hate relationship with information technology: We can't live without it, but at the same time, we find it difficult to live with. The problem of making technology comfortable does have solutions, but we can't buy them now; they will be available to us only if we drop a lot of the baggage of the past. The customary, desktop-based, applications-oriented interfaces turn out to be part of the problem. This book offers some alternatives. After all, computer problems are not like the weather: We can do something about them. Given the prevalence of the Internet and the obvious importance of products that facilitate group interaction, it may seem odd that The Humane Interface concentrates on single-user interface design. One reason is that the design of single-user interfaces is not a solved problem. The primary reason is that the quality of any interface is ultimately determined by the quality of the interaction between one human and one system between you and it. If a system's one-on-one interaction with its human user is not pleasant and facile, the resulting deficiency will poison the performance of the entire system, however fine that system might be in its other aspects. | 
