“This is a huge revision. I expect I have made mistakes. Please leave corrections and suggestions in the Comments at the end. If you have better examples than I’m using, please include them as well, but give me enough information about them, including links or cites, that I can make use of them. This revision features new examples and discussion involving mobile, wearables, and Internet-connected smart devices. However, the naming and organization remains the same except for three changes: I have shortened the name of one principle to extend its reach: ‘Color Blindness’ is now simply Color and includes more than just color blindness. I’ve added one new principle, Aesthetics, and brought back two old principles, Discoverability and Simplicity. I dropped them from the list more than a decade ago when they had ceased to be a problem. Problems with Discoverability, in particular, have come roaring back. What has changed greatly is the level of detail: You will find many new sub-principles within each category, along with far more explanation, case studies, and examples.”

(Bruce Tognazzini)