Users spend most of their time on other sites, and they prefer your site to work the same way as all the other sites they already know.
The time to acquire a target is a function of the distance to and size of the target.
The time it takes to make a decision increases with the number and complexity of choices available.
The average person can keep only 7 (± 2) items in their working memory.
Be conservative in what you do, be liberal in what you accept from others.
People judge an experience largely based on how they felt at its peak and at its end, rather than on the total sum or average of every moment of the experience.
Users often perceive aesthetically pleasing design as design that’s more usable.
When multiple similar objects are present, the one that diers from the rest is most likely to be remembered.
Tesler’s law, also known as the law of conservation and complexity, states that for any system there is a certain amount of complexity that cannot be reduced.
Productivity soars when a computer and its users interact at a pace (<400 ms) that ensures that neither has to wait on the other.