The document discusses several design principles from various sources, including principles for web design, interface design, inclusive design, accessibility, longevity, and others. It provides lists of principles with short descriptions or examples for each. The overall document serves to collect and organize key principles that can be referred to for guidance in design work.

1. The Robustness Principle
Be conservative in what you send; be liberal in what you accept.
The Pareto Principle
80% of the effects come from 20% of the causes.
The Principle of Least Surprise
When two elements of an interface conflict, or are ambiguous, the behaviour should be that which will least surprise the
user.
The DRY Principle
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
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2. These statements of architectural principle explain the thinking behind the specifications. These are personal notes by
Tim Berners-Lee: they are not endorsed by W3C. They are aimed at the technical community, to explain reasons, provide
a framework to provide consistency for for future developments, and avoid repetition of discussions once resolved.
Simplicity
1.
Modular Design
2.
Being part of a Modular Design
3.
Tolerance
4.
Decentralization
5.
Test of Independent Invention
6.
Principle of Least Power
7.
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3. Why doesn't HTML include tags for style? Why can't you put text inside SMIL? Why doesn't CSS include commands to
transform a document? Why, in short, does W3C modularize its specification and why in this particular way? This essay
tries to make explicit what the developers in the various W3C working groups mean when they invoke words like
efficiency, maintainability, accessibility, extensibility, learnability, simplicity, longevity, and other long words ending in
-y.
Maintainability
1.
Modularity
2.
Minimum redundancy
3.
Accessibility
4.
Device-independency
5.
Internationality
6.
Extensibility
7.
Learnability
8.
Readability
9.
Efficiency
10.
Binary or text format
11.
Implementability
12.
Simplicity
13.
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4. Longevity
14.
Backwards compatibility
15.
Interoperability
16.
Repurposing of content
17.
Timeliness
18.
Use what is there
19.
Design by committee
20.
Expertise
21.
Brevity
22.
Stability
23.
Robustness
24.
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5. Good design is innovative
1.
Good design makes a product useful
2.
Good design is aesthetic
3.
Good design makes a product understandable
4.
Good design is unobtrusive
5.
Good design is honest
6.
Good design is long-lasting
7.
Good design is thorough down to the last detail
8.
Good design is environmentally friendly
9.
Good design is as little design as possible
10.
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6. Be narrow
1.
Be different
2.
Be casual
3.
Be picky
4.
Be user-centric
5.
Be self-centered
6.
Be greedy
7.
Be tiny
8.
Be agile
9.
Be balanced
10.
(bonus!) Be wary
11.
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7. The following principles are fundamental to the design and implementation of effective interfaces, whether for
traditional GUI environments or the web. Of late, many web applications have reflected a lack of understanding of
many of these principles of interaction design, to their great detriment. Because an application or service appears on the
web, the principles do not change. If anything, applying these principles become even more important.
Anticipation
1.
Autonomy
2.
Color Blindness
3.
Consistency
4.
Defaults
5.
Efficiency of the User
6.
Explorable Interfaces
7.
Fitts’ Law
8.
Human Interface Objects
9.
Latency Reduction
10.
Learnability
11.
Metaphors
12.
Protect Users’ Work
13.
Readability
14.
Track State
15.
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8. Visible Navigation
16.
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9. Interfaces exist to enable interaction between humans and our world. They can help clarify, illuminate, enable, show
relationships, bring us together, pull us apart, manage our expectations, and give us access to services. The act of
designing interfaces is not art and they are not monuments unto themselves. Interfaces do a job and their effectiveness
can be measured. They are not just utilitarian, however. The best interfaces can inspire, evoke, mystify, and intensify our
relationship with the world.
Interfaces exist to enable interaction
1.
Clarity is job #1
2.
Conserve attention at all costs
3.
Keep users in control
4.
Direct manipulation is best
5.
One primary action per screen
6.
Keep secondary actions secondary
7.
Provide a natural next step
8.
Appearance follows behavior (aka form follows function)
9.
Consistency matters
10.
Strong visual hierarchies work best
11.
Smart organization reduces cognitive load
12.
Highlight, don't determine, with color
13.
Progressive disclosure
14.
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10. Help people inline
15.
A crucial moment: the zero state
16.
Existing problems are most valuable
17.
Great design is invisible
18.
Build on other design disciplines
19.
Interfaces exist to be used
20.
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11. Inclusive Design is where innovation and imagination flourish. Meeting the needs of the widest variety of people does not
inhibit creativity. It opens our minds and inspires excellence.
Equitable: Be welcoming.
1.
Flexible: Provide options.
2.
Straightforward: Be obvious and not ambiguous.
3.
Perceptible: Don’t assume anything.
4.
Informative: Be timely, predictable, uncomplicated and precise.
5.
Preventative: Provide easy to follow instructions and gently guide users.
6.
Tolerant: Handle errors respectfully.
7.
Effortless: Don’t make demands or place restrictions on your users.
8.
Accommodating: Be approachable, uncluttered and give people room to manoeuvre.
9.
Consistent: Follow standards, guidelines, conventions and best practices.
10.
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12. Reduce the cost of using and acting on the evidence in the archive.
Engage new people in the records.
Preserve access to the evidence for as long as possible in as many ways as possible.
Use open standards
1.
Think long term
2.
Stay small, let others create meta-collections
3.
Strive for universal accessibility, be accessible by default
4.
Store the original record, present its essense over its resolution
5.
Work together
6.
Be wary of other people’s ideas
7.
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13. Google’s mission is to organize the world’s information and make it universally accessible and useful.
Focus on the user and all else will follow.
1.
It’s best to do one thing really, really well.
2.
Fast is better than slow.
3.
Democracy on the web works.
4.
You don’t need to be at your desk to need an answer.
5.
You can make money without doing evil.
6.
There’s always more information out there.
7.
The need for information crosses all borders.
8.
You can be serious without a suit.
9.
Great just isn’t good enough.
10.
Focus on people their lives, their work, their dreams.
1.
Every millisecond counts.
2.
Simplicity is powerful.
3.
Engage beginners and attract experts.
4.
Dare to innovate.
5.
Design for the world.
6.
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14. Plan for today’s and tomorrow’s business.
7.
Delight the eye without distracting the mind.
8.
Be worthy of people’s trust.
9.
Add a human touch.
10.
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15. These guidelines are intended for people building digital services for the GOV.UK domain. … We believe that the work
should do the talking, so underneath each of the principles there are examples of how we have applied that thinking in
the work released so far.
Start with needs
1.
Do less
2.
Design with data
3.
Do the hard work to make it simple
4.
Iterate. Then iterate again.
5.
Build for inclusion
6.
Understand context
7.
Build digital services, not websites
8.
Be consistent, not uniform
9.
Make things open: it makes things better
10.
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16. Design for how people actually behave
1.
Assume people don’t care
2.
Always lead to action
3.
Aim for lasting relationships, not one-night stands
4.
Build for everyone… who receives a utility bill
5.
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17. HTML5 defines the fifth major revision of the core language of the World Wide Web, HTML.
Support existing content
i.
Degrade gracefully
ii.
Do not reinvent the wheel
iii.
Pave the cowpaths
iv.
Evolution not revolution
v.
1.
Solve real problems
i.
Priority of constituencies
ii.
Secure by design
iii.
Separation of concerns
iv.
DOM consistency
v.
2.
3.
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18. Well-defined behavior
i.
Avoid needless complexity
ii.
Handle errors
iii.
Media independence
i.
Support world languages
ii.
Accessibility
iii.
4.
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19. A set of simple, open data formats built upon existing and widely adopted standards.
Solve a specific problem
1.
Start as simple as possible
2.
Design for humans first, machines second
3.
Reuse building blocks from widely adopted standards
4.
Modularity / embeddability
5.
Enable and encourage decentralized and distributed development, content, services
6.
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20. The guidelines and Success Criteria are organized around the following four principles, which lay the foundation
necessary for anyone to access and use Web content. Anyone who wants to use the Web must have content that is:
Perceivable
It can't be invisible to all of their senses.
Operable
The interface cannot require interaction that a user cannot perform.
Understandable
The content or operation cannot be beyond their understanding.
Robust
As technologies and user agents evolve, the content should remain accessible.
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21. An open source content management platform
Make the most frequent tasks easy and less frequent tasks achievable.
1.
Design for the 80%
2.
Privilege the Content Creator
3.
Make the default settings smart
4.
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22. Instead of reviewing restaurants, you can recommend your favorite dishes and see what others have recommended
wherever you go.
It’s about dishes, not just restaurants
1.
It’s visual
2.
It’s positive
3.
It’s global
4.
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23. It's what enables us to debate whether something “Is Facebook” or “Isn't Facebook,” it's what allows us to evaluate
whether anything we’re designing could be improved.
Universal
1.
Human
2.
Clean
3.
Consistent
4.
Useful
5.
Fast
6.
Transparent
7.
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24. After a few weeks sketching and debating, we stepped back and created some simple design principles before moving
forward:
Interaction is the basic unit of design.
Transitional interfaces are easier to learn and more pleasant to use.
Interactions should be delightful and surprising.
Focus the user on one primary action at a time.
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25. These are the principles that Danny Hillis used in the initial stages of designing a 10,000 Year Clock. We have found
these are generally good principles for designing anything to last a long time.
Longevity
With occasional maintenance, the clock should reasonably be expected to display the correct time for the next 10,000
years.
Maintainability
The clock should be maintainable with bronze-age technology.
Transparency
It should be possible to determine operational principles of the clock by close inspection.
Evolvability
It should be possible to improve the clock with time.
Scalability
It should be possible to build working models of the clock from table-top to monumental size using the same design.
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26. Design Principles http://principles.adactio.com/
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