The Fundamental Principles of Interaction

The rice and beans to grow strong and healthy.

Minha mãe sempre disse que criança que não come direito não cresce.

After spending some time trying to figure out some complex problems of my work, asking myself if I had something wrong with my brain for my difficulty to find answers, or making the right questions, I decided to come back to the basics: Read fundamental theory.

I started with Don Norman’s book The Design of Everyday Things and realised how important is to really understand this basic knowledge. That’s why my intention is to continue studying this basic material, writing the most important things here, as a way to never forget and to help the UX community somehow. A solid basis is essential to solve any big challenge.

That’s life when you don’t have a solid basis.

By the moment I started the book, I saw the fundamental principles of interaction. Why not start with them?

This post will be updated regularly with each principle link, that I’ll explain with details, examples and perceptions. I hope that can help people that, just like me, get their ass kicked (intellectually) by brilliant mentors.

Norman says that everything is a matter of experience. The experience is the element that determines how meaningful the interactions will be in people’s mind.

That means it’s more likely to remember a bad experience that a good one… and this is your responsability, young designer.

When we interact with a product, we need to understand it all. Norman says that the two most important characteristics of a good design are:

DISCOVERABILITY

Which actions are possible on this product and how/when can we use it?

UNDERSTANDING

What do this all mean? How this product should be used? Why this product even exists? It’s the full understanding, that comes naturally when there is a good discoverability.

He even says:

“ Design in concerned with how things work, how they are controlled, and the nature of interaction between people and technology.”

Good design?

Many products fail on their discoverability, like dishing machines, that we know what’s their meaning and that you need to the dishes inside it, but to understand the possible actions, we practically need to go to a “dish washer university”. There’s just too many buttons/options. That’s why the most of us just memorize one or two main commands and dont’t dare to explore others… what if we break it? A bad experience that let us with that dumb feeling.

It’s easy to understand that and start to analyse every product we use to study… but we can go further, specially of we want to learn hoe to apply this in the products we work with.

And that’s the point when we start to explore the 6 fundamental principles of interaction, where the first 5 are fundamental concepts of psychology. My intention is to talk specifically of each one in the next posts:

Affordances

It’s the relationship between the object proprieties and the user capabilities to understand how the object can be used. It’s one of the most difficult examples, because it’s something really intuitive… a classic door knob can be an affordance example, because you look and naturally understand that you can twist it.

Signifiers

This one is wrongly defined as affordance sometimes. It’s an artifitial way to communicate where and how an action should be made. A “pull” or “push” sign in a door is a good example. It’s not intuitive, but got this relation between characteristics and capacity to determine the action.

Constraints

The limitations or restrictions that gives us tips on what we can and can’t do. They prevent many errors. An example that I like is some door, made to push, without a knob. That way, you only have one option. A limitation that guides us perfectly.

Mappings

They’re signs that guides us on actions. The buttons to turn up/down the volume are great examples. Normally they’re side by side or one on the top of the other. There’s the signifier, the volume icon and the arrows (+ and -signs), but the position of the buttons guides us.

Feedback

This is a classic, that makes us happy when we receive it fast and make us press the same button 200 times if it takes too long and we don’t know it. Pressing an elevator button, we got the light feedback, saying our action worked.

Conceptual Model

This is the explanation, simplified, of how somethinf works. It’s an inception, if you think: Your computer operational system has a womderful conceptual model, that allows you to see files, folders and icons. The truth is: You don’t put files inside a folder… it’s all about code.

Norman says that the first five elements generates the discoverability, and the Conceptual Model, the final understanding.

This principles are the rice and beans for any Product Designer, so it comes the time when you realise that, if you don’t know this basics, this first steps, how can you expect to run a marathon through complex problems?

That’s it! I hope you have enjoyed this introduction and as soon as possible, I’ll start the next one, where I’ll talk about Affordances :)