Anti-mac Interface
Dona Gentner
Jakob Nielsen
[Sun Microsystems]
Background
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The Macintosh designed to be "the computer for the
rest of us“
"the first personal computer good enough to be
criticized."
Alan Kay
Prevailing constraints:
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Audience – naïve users
Narrow range of applications – undiscovered territory
Weak computational resources
Highly impoverished communication channels
No networking
How about now?
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Macintosh human interface
design principles
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Metaphors
Direct Manipulation
See-and-Point
Consistency
WYSIWYG
User Control
Feedback & Dialog
Forgiveness
Perceived Stability
Aesthetic Integrity
Modelessness
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Macintosh human interface design principles:
Metaphor
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Desktop, village, building metaphors
Clunky indirectness
Navigationally cumbersome
E.g. Phelp’s tractor (1901)
E.g. Mac multiple trashcans
Can limit designer’s creativity
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E.g. Sun documentation
Invalid assumptions regarding user audience
experiences
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Macintosh human interface design principles:
Direct Manipulation
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Works well for small number of objects
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Operating at atomic level only
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Scripting mechanism required
 E.g. Photoshop actions
Constrained to precision of hand/eye/mouse
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Difficult to direct high-level operations
 E.g. selecting a range of files of certain characteristics
Language and maths can be more precise
Users may not know what to manipulate
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Willing to delegate control to ‘single-click’ operation
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Macintosh human interface design principles:
See-and-Point
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Interaction by pointing and clicking on objects
faculty with expressive language lost
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Keyboard modifiers equivalent to grunts
Cannot communicate with objects that
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Are not immediately visible
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Don’t yet exist
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E.g. all files less than 1 week old
E.g. future messages from my boss
Are unknown
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E.g. any guides to restaurants in Boston
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Macintosh human interface design principles:
Consistency
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Basic advantage is the hope that learning will
be reduced if objects with a similar function
always look and behave the same
How about pens?
Rich and fine-grained representation of
objects in the real world helps us distinguish
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Macintosh human interface design principles:
WYSIWYG
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Usually WYSIATI (What You See Is All There
Is)
Document’s rich semantic structure lost
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E.g. italicised word could indicate biblio entry,
quote, or simple emphasis
SGML preserves semantic attributes
Not appropriate for modern communications
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E.g. same info presented on desktop, mobile
browsers, screen reader for disabled etc.
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Macintosh human interface design principles:
User Control
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User alone should initiate and control actions
What about delegation as in real-world?
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People bad at vigilance tasks
E.g. backups, saving document, forgetting
meetings
We participate in the Internet with little control
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Macintosh human interface design principles:
Feedback and Dialog
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The computer interface should provide the
user with clear and immediate feedback on
any actions initiated by the user
Master-Apprentice model preferable
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Provide a spectrum of feedback
Diminish feedback as experience grows
‘No news is good news’
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Macintosh human interface design principles:
Forgiveness
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States that user actions should generally be
reversible and that users should be warned if
they try to do something that will cause
irreversible data loss.
E.g. Mac Trash can circular problem
Underlying problem is meager understanding
of the interaction history
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Stateless interface is inadequate
Computer needs to build a deeper model of our
intentions and history.
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Macintosh human interface design principles:
Perceived Stability
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Elements in the computer interface should
not be changed without the user's
involvement
“Children like stability”
Computer games eschew stability
Internet thrives on ‘new-ness’
Growing maturity of users
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less insecurity
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Macintosh human interface design principles:
Aesthetic Integrity
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States that the graphic design of the interface
should be simple, clean, and consistent
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Partly due to limited expressiveness of current
computers
E.g. consider city designed by a single architect
with a consistent visual appearance
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Difficult to navigate and boring
Richer more detailed designs are
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Interesting
Provide landmarks
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Macintosh human interface design principles:
Modelessness
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Computer interface should not have distinct
modes that restrict the user's actions
depending on the mode he or she is in
However user cannot cope with everything at
once
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need the interface to narrow their attention and
choices so they can find the information and
actions they need at any particular time
real life is highly moded
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