Technology usually provides a series of tradeoffs. Each asset is offset by a deficit...A major problem occurs when those who suffer from technology's defecits and those who benefit are not the same people.

The designer has an obligation to provide an appropriate conceptual model for the way that the device works. It doesn't have to completely accurate but it has to be sufficiently accurate that it will help in both the learning of the operation and also dealing with novel situations.

The argument is not between adding features and simplicity, between adding capability and usability. The real issue is about design: designing things that have the power required for the job while maintaining understandabili ty, the feeling of control, and the pleasure of accomplishment.

I think there is a tendency in science to measure what is measurable and to decide that what you cannot measure must be uninteresting.

So what does a good teacher do? Create tension - but just the right amount.

User-centered design means working with your users all throughout the project.

In design it is important to shoe the effect of an action. ... Feedback is critical.