Introduction
1. Cognitive Load: Keeping It Simple
What it is: Cognitive load refers to the mental effort required to process information. A cluttered or complex design overwhelms users, leading to frustration and drop-offs.
How to apply it:
• Use progressive disclosure (showing only necessary information at a given time).
• Keep interfaces clean and minimal to avoid distractions.
• Follow Hick’s Law: The more choices users have, the longer they take to decide—so keep it simple.
Example: Google’s homepage is a perfect example of minimal cognitive load—just a search bar and logo.
2. Fitts’s Law: Making Interactions Effortless
What it is: The time required to move to a target area (like a button) depends on its size and distance. Larger and closer elements are easier to click.
How to apply it:
• Ensure important buttons (like CTAs) are large and easy to reach.
• Place frequently used controls within easy reach of the user’s natural hand movements.
• Avoid small, hard-to-click elements.
Example: Mobile navigation bars are usually placed at the bottom for easy thumb access.
3. Gestalt Principles: Designing for Perception
What it is: Gestalt psychology explains how people perceive visual elements as a whole rather than in parts.
How to apply it:
• Proximity: Group related elements together (e.g., form fields).
• Similarity: Use consistent colors and shapes for related actions.
• Closure: Use partial visuals that the brain fills in (e.g., dotted lines forming a shape).
• Figure-Ground: Ensure clear contrast between the background and interactive elements.
Example: Apple’s UI design relies on clear visual hierarchy and grouping.
4. Hick’s Law: Reducing Decision Fatigue
What it is: The more choices users have, the longer it takes for them to make a decision.
How to apply it:
• Limit the number of choices in menus and navigation.
• Use default options to guide users toward common actions.
• Implement step-by-step processes (e.g., wizards, onboarding flows).
Example: Amazon’s “Buy Now” button reduces friction by skipping unnecessary steps.
5. The Zeigarnik Effect: Encouraging Task Completion
What it is: People remember incomplete tasks better than completed ones, which can be leveraged to improve user engagement.
How to apply it:
• Show progress bars in onboarding and checkout flows.
• Use visual indicators (e.g., checkmarks) for completed steps.
• Encourage users to finish incomplete profiles with reminders.
Example: LinkedIn’s profile completion meter motivates users to fill in their details.
6. The Peak-End Rule: Creating Memorable Experiences
What it is: Users judge an experience based on its most intense moment (peak) and the ending.
How to apply it:
• Design delightful microinteractions and animations.
• Provide a pleasant final step (e.g., a thank-you message after a purchase).
• Ensure a smooth checkout or sign-up experience.
Example: Duolingo uses fun animations and rewards at the end of each lesson.