Mayhew's Book (chapt. 9)

Designing Direct Manipulation Interfaces

• Provide visual feedback for position, selection and movement, and clear feedback for modes.

• Provide an alternative interface for high-frequency, expert users.

• Choose a consistent icon design scheme.

• Design icons to be concrete and familiar.

• Design icons in a set to be visually and conceptually distinct.

• Avoid excessive detail in icon design.

• Design icons to communicate object relations and attributes whenever possible.

• Accompany icons with names.

• Limit the number of icon types to 12 if possible, but at most to 20.

• Allow users to choose between iconic and text display of objects and actions.