Design of Everyday Things - Norman, Don [99]
When I use a direct manipulation system—whether for text editing, drawing pictures, or creating and playing games—I do think of myself not as using a computer but as doing the particular task. The computer is, in effect, invisible. The point cannot be overstressed: make the computer system invisible. This principle can be applied with any form of system interaction, direct or indirect.
THE INVISIBLE COMPUTER OF THE FUTURE
Consider what the computer of the future might look like. Suppose I told you it wouldn’t even be visible, that you wouldn’t even know you were using one? What do I mean? Well, this is already true: you use computers when you use many modern automobiles, microwave ovens, and games. Or CD players and calculators. You don’t notice the computer because you think of yourself as doing the task, not as using the computer.22
In the same sense, you don’t go to the kitchen to use an electric motor; you go to use the refrigerator, or the blender, or the dishwasher. The motors are part of the task, even in the case of the blender, mixer, or food processor, which are essentially pure motors and the specialized attachments they drive.
The computer of the future is perhaps best illustrated by my imaginary perfect calendar. Suppose I am home one evening, deciding whether to accept an invitation to attend a conference next May. I pick up my appointment calendar and turn to the appropriate page. I tentatively decide that I can attend and pencil in the topic. The calendar flashes at me and displays a note reminding me that the university will still be in session during that period and that the trip overlaps my wife’s birthday. I decide that the conference is important, so I make a note to check whether I can get someone to take over my classes and to see whether I can leave the conference early for the birthday. I close the calendar and get back to other things. The next day, when I arrive at my office 1 find two notes on my message screen: one to find a substitute for my classes next May, the other to check with the conference organizers to see if I can leave early.
This imaginary calendar looks like a calendar. It’s about the size of a standard pad of paper, it opens up to display dates. But it really is a computer, so it can do things that today’s appointment calendar cannot. It can, for example, present its information in different formats: it can display the pages compressed so that a whole year fits on one page; it can expand the display so that I see a single day in thirty-minute intervals. Because I frequently use my calendar in conjunction with my travels, the calendar is also an address book, notepad, and expense account record. Most important, it can also connectitself to my other systems (via a wireless infrared or electromagnetic channel). Thus, whatever I enter into the calendar gets transmitted to my office and home systems so that they are always in synchrony. If I make an appointment or change someone’s address or telephone number on one system, the others get told. When I finish a trip, the expense record can be transferred to the expense account form. The computer is invisible, hidden beneath the surface; only the task is visible. Although I may actually be using a computer, I feel as if I am using my appointment calendar.
CHAPTER SEVEN
USER-CENTERED DESIGN
OFF THE LEASH By W.B. Park
“Darn these hooves! I hit the wrong switch again! Who designs these instrument panels, raccoons?”
The point of POET