Miller’s Law
The number of objects an average person can hold in working memory is about seven, also known as The Magical Number Seven, Plus or Minus Two.
Fitts’s Law
The longer the distance and the smaller the target’s size, the longer it takes.
Jakob’s Law
Users spend most of their time on other sites. This means that users prefer your site to work the same way as all the other sites they already know.
Law of Proximity
Things closer to each other appear more related than things farther apart.
Parkinson’s Law
Work expands so as to fill the time available for its completion.” If something must be done in a year, it’ll be done in a year.
Von Restorff Effect
When multiple similar objects are present, the one that differs from the rest is most easy to remember.
Zeigarnik Effect
Incomplete tasks are most likely to be remembered. You could help the users remember certain uncompleted tasks by adding a simple progress bar.
Hick’s Law
Time for decision making depends on how many and how complex the choices are.
Serial Position Effect
This effect states that the first and the last terms are most likely remembered.
Law of Common Region
The law of common region expresses that elements are grouped together when they share an area with a clear boundary between them.
Goal-Gradient Effect
As people get closer to a reward, they speed up their behavior to get to their goal faster.
Law of Pragnanz
When you’re presented with a set of ambiguous or complex objects, your brain will make them appear as simple as possible.
Tesler’s Law
Tesler argues that an engineer should spend extra time reducing complexity on the application instead of making users spend more time on the task they’re trying to perform.
Peak-End Rule
if the peak and the end are good, people will conclude that the entire experience was good.
Aesthetic-Usability Effect
People tend to believe that things that look better will work better even if they aren’t actually more effective or effecient.
Doherty Threshold
If a response appears after the 400 ms threshold, users eventually become disinterested according to a study done in the late 1970s.
Law of Similarity
The human eye tends to perceive similar elements in a design as a complete picture, shape, or group, even if those elements are separated.
Pareto Principle
For many events, roughly 80% od the effects come from 20% of the causes.
Postel’s Law
Be conservative in what you do, be liberal in what you accept from others. The more you plan the more resilient the design will be.
Occam’s Razor
Simplicity is better than complexity.
