The Design of Everyday Things Summary

Exploring “The Design of Everyday Things”: My Notes and Reflections

Here are my notes and quotes on The Design of Everyday Things by Don Norman. My notes are casual and include what I believe are the essential concepts, ideas, and insights from the book, along with direct quotes from the author.

This book covers everyday things, focusing on the interplay between technology and people to ensure that the products actually fulfill human needs while being understandable and usable. The products should also be delightful and enjoyable, which means that not only must the requirements of engineering, manufacturing, and ergonomics be satisfied, but attention must be paid to the entire experience, which means the aesthetics of form and the quality of interaction.

The Psychology of Design: Communication and Understanding

Much of the design is done by engineers who are experts in technology but limited in their understanding of people. “We are people ourselves,” they think, “so we understand people.” But in fact, we humans are amazingly complex. Those who have not studied human behavior often think it is pretty simple. Engineers, moreover, make the mistake of thinking that logical explanation is sufficient: “If only people would read the instructions,” they say, “everything would be all right.” Engineers are trained to think logically.

Design is concerned with how things work, how they are controlled, and the nature of the interaction between people and technology. When done well, the results are brilliant, pleasurable products. When done badly, the products are unusable, leading to great frustration and irritation.

Good design starts with an understanding of psychology and technology. Good design requires good communication, especially from machine to person, indicating what actions are possible, what is happening, and what is about to happen. Communication is especially important when things go wrong. Designers need to focus their attention on the cases where things go wrong, not just on when things work as planned. The understanding comes about primarily through observation, for people themselves are often unaware of their true needs, even unaware of the difficulties they are encountering.

Getting the specification of the thing to be defined is one of the most difficult parts of the design, so much so that the HCD principle is to avoid specifying the problem as long as possible but instead to iterate upon repeated approximations. This is best done through rapid test of ideas, and after each test modifying the approach and the problem definition.

Fundamental Concepts of Human-Centered Design

The book introduces several key concepts that form the foundation of human-centered design. These principles, when applied correctly, result in products that are not only functional but also intuitive and enjoyable to use.

Discoverability and Understanding

Two of the most important characteristics of good design are discoverability and understanding. Discoverability refers to whether it is possible to even figure out what actions are possible and where and how to perform them. Understanding, on the other hand, concerns what it all means: How is the product supposed to be used? What do all the different controls and settings mean?

Human-Centered Design (HCD)

Human-Centered design is a design philosophy. It means starting with a good understanding of people and the needs that the design is intended to meet. This understanding comes about primarily through observation, for people themselves are often unaware of their true needs, even unaware of the difficulties they are encountering. Getting the specification of the thing to be defined is one of the most difficult parts of the design, so much so that the HCD principle is to avoid specifying the problem as long as possible but instead to iterate upon repeated approximations. This is done through rapid tests of ideas, and after each test modifying the approach and the problem definition. The results can be products that truly meet the needs of people.

The Five Fundamental Psychological Concepts

Discoverability results from appropriate application of five fundamental psychological concepts:

• Affordances: relationship between the properties of an object and the capabilities of the agent that determines just how the object could possibly be used.
• Signifiers: communicate where the action should take place. Good design requires, among other things, good communication of the purpose, structure, and operation of the device to the people who use it.
• Constraints: providing physical, logical, semantic, and cultural constraints guides actions and eases interpretation.
• Mapping: relationship between controls and their actions. The relationship between a control and its results is easiest to learn wherever there is an understandable mapping between the controls, the actions, and the intended result.
• Feedback: communicating the results of an action. Feedback must be immediate, informative and poor feedback can be worse than no feedback at all. Feedback is essential but not when it gets in the way of others things, including a calm and relaxing environment.

Conceptual Models

Conceptual Models are an explanation, usually highly simplified, of how something works. It doesn’t have to be complete or even accurate as long as its useful. Good conceptual models are the key to understandable, enjoyable products: good communication is the key to good conceptual models.

Human Error: A Design Opportunity

Norman argues that human error is, in most cases, a design error. Instead of blaming the user, we should analyze why the error occurred and redesign the product or procedures to prevent it from happening again.

Two Types of Errors: Slips and Mistakes

There are two main types of errors:

• Slips: a person intends to do one action and ends up doing something else. Slips most frequently occur when the conscious mind is distracted. One way to minimize slips is to ensure that people always pay close, conscious attention to the acts being done. The best way of mitigating slips is to provide perceptible feedback about the nature of the action being performed, then very perceptible feedback describing the new resulting state, coupled with a mechanism that allows the error to be undone.

• Mistakes: occurs when the wrong goal is established or the wrong plan is formed. To understand human error, it is essential to understand social pressure and other contextual factors.

Designing for Error

Many systems compound the problem by making it easy to err but difficult or impossible to discover error or to recover from it. It should not be possible for one simple error to cause widespread damage. Here is what should be done:

• Understand the causes of error and design to minimize those causes.
• Do sensibility checks. Does the action pass the “common sense” test?
• Make it possible to reverse actions—to “undo” them—or make it harder to do what cannot be reversed.
• Make it easier for people to discover the errors that do occur, and make them easier to correct.
• Don’t treat the action as an error; rather, try to help the person complete the action properly. Think of the action as an approximation to what is desired.

The Seven Stages of Action

Norman introduces a useful framework for understanding human action:

1. Goal (form the goal) - what do I want to accomplish?
2. Plan (the action) - What are the alternative action sequences?
3. Specify (an action sequence) - What action can I do now?
4. Perform (the action sequence) - How do I do it?
5. Perceive (the state of the world) - What happened?
6. Interpret (the perception) - What does it mean?
7. Compare (the outcome with the goal) - Is this okay? Have I accomplished my goal?

Final Reflections: The Permanence of Design Principles

With massive change, a number of fundamental principles stay the same. Human beings have always been social beings. Social interaction and the ability to keep in touch with people across the world, across time, will stay with us. The design principles of this book will not change, for the principles of discoverability, of feedback, and of the power of affordances and signifiers, mapping, and conceptual models will always hold. Even fully autonomous, automatic machines will follow these principles for their interactions. Our technologies may change, but the fundamental principles of interaction are permanent.

Cognition and emotion are tightly intertwined, which means that the designers must design with both in mind. Precise behavior can emerge from imprecise knowledge for four reasons:

• Knowledge is both in the head and in the world.
• Great precision is not required.
• Natural constraints exist in the world.
• Knowledge of cultural constraints and conventions exists in the head.

The Power of Standardization

Standardization is indeed the fundamental principle of desperation: when no other solution appears possible, simply design everything the same way, so people only have to learn once. The standards should reflect the psychological conceptual models, not the physical mechanics. Standardization is one type of cultural constraint. With standardization, once you have learned to drive one car, you feel justifiably confident that you can drive any car, anyplace in the world. Standardization provides a major breakthrough in usability.

Making Memory Unnecessary

Make memory unnecessary: put the required information in the world. Even systems that do not use menus need to provide some structure: appropriate constraints and forcing functions, natural good mapping, and all the tools of feedforward and feedback. The most effective way of helping people remember is to make it unnecessary.

In conclusion, “The Design of Everyday Things” remains an essential read for anyone interested in design, technology, and human-computer interaction. Its principles, though formulated decades ago, remain incredibly relevant in our increasingly digital world. The book teaches us that good design is not just about aesthetics or functionality—it’s about understanding human psychology and creating products that work seamlessly with how people naturally think and behave.