Mandel's golden rules of UID
1. Place users in control
- Use modes judiciously (modeless)
- Allow users to use either keyboard or mouse (flexible)
- Allow users to change focus (interruptible)
- Display descriptive messages and text (helpful)
- Provide immediate and reversible actions, and feedback (forgive)
- Provide meaningful paths and exits (navigable)
- Accommodate users with different skill levels (accessible)
- Make the user interface transparent (facilitative)
- Allow users to customize the interface (preferences)
- Allow users to directly manipulate interface objects (interactive)
2. Reduce users' memory load
- relieve short term memory (remember)
- rely on recognition, not recall (recognition)
- provide visual clues (inform)
- provide defaults, undo, and redo (forgiving)
- provide interface shortcuts (frequency)
- promote an object-action syntax (intuitive)
- use real-world metaphors (transfer)
- use progressive disclosure (context)
- promote visual clarity (organize)
3. Make the interface consistent
- sustain the context of users' tasks (continuity)
- maintain consistency within and across products (experience)
- keep interaction results the same (expectations)
- provide aesthetic appeal and integrity (attitude)
- encourage exploration (predictability)
Source: The Elements of User Interface Design, by Theo Mandel, Wiley Publ, 1997.