Lecture 3 - Notes

January 11, 2016

Norman's Principals of Design

Visibility

• The correct parts must be visible and they must convey the correct message
• Natural signals are naturally interpreted
• Visibility problems occur when clues are lacking
• The mapping between intended actions and actual operations should be visible

Mappings

• Controls and displays should exploit natural mappings
• Natural mappings take advantage of physical analogies and cultural standards

Scaffolding can cause problems when it comes to remembering where things are.

Affordances allow us to imbue objects and controls with purpose, e.g., buttons push. In virtual interfaces we don't have "real" affordances since the interface lacks dimension. However using visual effects we can create "perceived" affordances.

Feedback

• Sending information back to the user about what has been done
• Includes sound, highlighting, animation and combinations of these

Constraints

• Restricting the possible actions that can be performed
• Helps prevent user from selecting incorrect options
• Three main types (Norman, 1999)
• physical
• cultural
• logical

Consistency

• Design interfaces to have similar operations and use similar elements for similar tasks
• Main benefit is consistent interfaces are easier to learn and use

Example

Always use ctrl key plus first initial of the command for an operation

ctrl+C, ctrl+S, ctrl+O