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- Intuitive software uses readily transferred, existing skills.
- Use/create visual idioms instead of metaphors.
Idioms are easy to learn, and (because they are distinctive) easy to remember.
This article is inspired by the "Intuitive=Familiar" article on Bruce Tognazzini's website.
Bits of text have been taken from this, as well as from articles by Jef Raskin and Jakob Neilsen.
Websters (online) probided the dictionary definitions.
intuition:
the power or faculty of attaining to direct knowledge
or cognition without evident rational thought or inference.
metaphor:
a figure of speech in which a word or phrase literally denoting one kind
of object or idea is used in place of another to suggest a likeness or
analogy between them.
idiom:
a group of words in a fixed order having a particular meaning, different from
the meanings of each word understood on its own.
Software designers are encouraged to produce software the is "intuitive" and "easy to use".
But what the hell does this mean?
We are said to "intuit" a concept when we seem to suddenly understand it without
any apparent effort or previous exposure to the idea.
The word "intuitive" is misleading when it is used to describe software
(for a start, the word used should be intuitable, not intuitive).
It implies that anyone will be able to use the software
without any prior experience or training.
This is simply not the case.
Objects that are claimed to be intuitive are in fact just easily learnt.
There's a great story about the intuitability of the mouse as an input device
(related by Jef Raskin in the article "Intuitive Equals Familiar",
Communications of the ACM, September 1994):
Many claims of intuitiveness, when examined, fail.
It has been claimed that the use of a computer's mouse is intuitive.
Yet it is far from that.
In one of the Star Trek series of science fiction movies,
the space ship's engineer has been brought back into our time,
where (when) he walks up to a Macintosh. He picks up the mouse,
bringing it to his mouth as if it were a microphone, and says:
"Computer, ..." The audience laughs at his mistake.
But that is just the whimsy of a screenwriter.
Or is it? I performed a deliberate experiment some years ago using one of the early
Apple Macintosh computers.
I loaded a children's program, The Manhole, where user interaction is strictly
(and cleverly) limited to "clicking" on various places on an image.
Clicking consists of moving the cursor to some location on the screen by moving
the mouse on a surface and momentarily pressing the only button on the mouse.
Clicking on certain places yields a new screen.
This cold description does not express the delight most people find in running
The Manhole program, but that is not relevant here.
My subject was an intelligent, computer-literate, university-trained teacher visiting
from Finland who had not seen a mouse or any advertising or literature about it.
With the program running, I pointed to the mouse, said it was "a mouse", and that one
used it to operate the program.
Her first act was to lift the mouse and move it about in the air.
She discovered the ball on the bottom, held the mouse upside down,
and proceeded to turn the ball.
However, in this position the ball is not riding on the position pick-offs and it does nothing.
After shaking it, and making a number of other attempts at finding a way to use it,
she gave up and asked me how it worked.
She had never seen anything where you moved the whole object rather than some part
of it (like the joysticks she had previously used with computers): it was not intuitive.
She also did not intuit that the large raised area on top was a button.
But once I pointed out that the cursor moved when the mouse was moved on the desk's surface
and that the raised area on top was a pressable button,
she could immediately use the mouse without another word.
The directional mapping of the mouse was "intuitive" because in this regard it
operated just like joysticks (to say nothing of pencils) with which she was familiar.
Raskin summarises:
Intuitive = uses readily transferred, existing skills.
Rather than attempting to build intuitive interfaces,
the best we can hope to do is design software that is quick to learn,
and we'll best achieve this by leveraging what users already know.
Metaphors are a potential minefield.
While Bruce Tognazzini still exhorts us to
"Build your design on a few simple driving concepts" and then
"Communicate those concepts through one or a few powerful metaphors"
(see "Intuitive vs Familiar" on his website),
Jakob Neilsen and Alan Cooper are critical.
The three classic problems with metaphors are:
-
The target domain has features not in the source domain
(e.g., telling the user that "a word processor is like a typewriter"
would not lead the user to look for the replace command).
-
The source domain has features not in the target domain
(a typewriter has the ability to mark up any form you receive in the mail,
but a user trying to do that on current computer systems will normally fail).
-
Some features exist in both domains but work very differently
(the treatment of white space representing space characters, tabs,
and line feeds is very different on typewriters and in word processors).
Therefore, users may have trouble seeing beyond the metaphor to use the
system in the ways it was intended.
User Interface metaphors are intended to indicate to users a set of potential functions;
that is, the set of functions the physical analogy would normally pro | 