Interaction Design — a comprehensive guide

Published in

The 31.5 Guy

10 min readJan 1, 2020

User-interface design, user-experience design, engineering design, information architecture design, industrial design, software design, interior design, business architecture design, graphic design, this design, that design, whew!

As if these terms weren’t enough, we are now burdened with another new pair of fancy words. But wait! “Interaction design” is, in no way, new — see it for yourself in this graph that shows the usage of this term from 2004. As a matter of fact, the usage of this term has rather gone down in recent years, since it was first coined by Bill Moggridge and Bill Verplank in the mid-1980s. But we can safely say that it’s value today, is as significant as ever.

Now that we know of this term, it is time to jump into this guide-of-sorts that will help you to get a clear understanding of this domain of design and help you move forward if you so desire. By the end of this story, you will have concise and precise answers to the following questions —

What is Interaction design?
What do I need to know to be an Interaction designer?
What tools would I need?
Are there any myths that I should not be misguided by?
Where can I find further resources?
What is the future scope of Interaction design?

Without further ado let’s get started!

1. What is Interaction design?

According to the Interaction Design Association (IxDA) —

Interaction Design (IxD) defines the structure and behaviour of interactive systems. Interaction Designers strive to create meaningful relationships between people and the products and services that they use, from computers to mobile devices.

Basically IxD is the practice of designing interactive services and products. This domain is linked closely to Human-Computer Interaction (or HCI). It is important to note that while, like other design domains, IxD does focus on the form and the physical design, IxD is primarily concerned more with behavioural studies. So it helps to reimagine things as they should be with respect to the users, instead of doing in-depth studies of how existing things have been designed. You might think that this field focuses on screen interfaces and how users interact, and you would be right — partly. IxD encompasses all areas of human interactions, including but not limited to organisations, cultures and societal systems.

Dimensions of IxD

There are 5 “dimensions” of design language that IxD draws on:

1D (Words) — this dimension defines interaction itself. Words are what enable people to interact in the first place.
2D (Visual representations) — this dimension has more in connection with perception. This includes diagrams, typography, graphics et cetera.
3D (Physical objects, or space) — this dimension lays the foundation for the environment. It is the space in which interactions occur.
4D (Time) — the 4th dimension we are all familiar with, it defines the dimension in which interactions progress, like a video playing.
5D (Behaviour) — this dimension entails the response of users to the product or interface.

You may think of the 5th dimension as a function of the other four dimensions, because different states of the 4 unique dimensions will result in unique measurements in the behaviour metric. A slight change in even one dimension may vastly alter the overall response to the given interaction.

As you may have understood by now, in the simplest of words, Interaction design deals with the ideation, creation and betterment of the dialogue between a user and an interface or product, through interaction. Various methodologies and principles are involved in this domain. Let us take a glimpse at some of them in the next section.

2. What do I need to know to be an Interaction designer?

Design is crafted through methodologies, based on principles, and flourishes with healthy doses of empathy, creativity and research — IxD is no different. As an interaction designer you do not restrict yourself to necessarily one domain or department, IxD roles are required in development and marketing teams as much as in a design team.

Are you inquisitive about how things work, and why they do? Are you unafraid to ask questions and get to the root? Can you mould existing concepts and visualise them in new ways so as to gain useful insights? If yes, you are on the right track.

The broad scope of work for an interaction designer is to understand user behaviour and make sure that given products or interfaces function properly when in use by the aforementioned users. In general, tasks would include doing thorough research and forming a design strategy, pointing out interactions of significance, developing PoCs (proof-of-concepts) and testing them out in the wild (not the “Animal Planet”-kind). As an interaction designer you should also be familiar with technological advancements, and stay up-to-date with current and upcoming trends.

Common methodologies

In IxD, there are methodologies that you should be familiar with. Some of the more popular ones are:

Goal-oriented design — that aims to cater to the requirements and wishes of users of a give product or service
Usability — basically looks into answering the question, “can this be used without any prior knowledge or information?”
Personas — help to represent the varied goals of a product and observed behaviours of users interacting with the product, during research
Cognitive dimensions — provide concepts like consistency, error-proneness and complexity of use, that help to give detailed descriptions of usages, consequently improving existing design models.

Popular principles

There are Laws in design that are supposed to guide you to make sure that your design has no fatal errors. Here are three of them:

Hick’s Law — states that more the number of choices in front of a person, the longer it will take her/him to make a decision. This is used commonly in IxD to make sure that there are only a few choices up front, so as to simplify the user’s process of decision-making and smoothen the experience.
Fitt’s Law — states that the amount of time needed for a user to move a cursor or pointer to a desired component, is a function of the distance to the component from the initial point, and the size of the component itself. So what you can glean from this, is that small buttons spaced widely is an example of bad IxD.
The Law of Conservation of Complexity — you may know this as Tesler’s Law. It states that all systems have processes, whose complexities cannot be simplified after a particular stage. So indirectly, you can make use of this principle to limit complexity (or simplicity) in an interface to optimise interaction performance of the users.

To be a good Interaction designer you should have in-depth knowledge of all such processes and principles, a passion for finding patterns and an understanding of user behaviour (through proper research), to be able to provide the users with the best experience of the interactions possible.

But the question that now arises is — how do I get these processes done? What do I use? Pen and paper? MATLAB? Canvas and paint-brushes? Let’s find out.

3. What tools would I need?

To understand the basis of the requirement of tools in IxD it is important to note that the crux of the goal is to communicate via conversation. Consequently, all tools that are at the disposal of an Interaction designer share one big purpose — to be able to communicate effectively.

A few of the popular tools and the purpose they serve, are:

Balsamiq Mockups — for making wireframes, basically paper prototyping taken online
LucidChart — for diagramming flowcharts, journey maps, wireframes and mockups
Axure RP — wireframe-to-prototype creation and, built-in collaboration and sharing
InVision Studio — for low- and medium-fidelity prototyping and real-time presentation
Figma or Sketch — for medium- and high- fidelity prototyping, making mockups and developer-handoff
Principle — for designing animations and micro-interactions
Patternry — for centralising resources in a shared code- and design-library

However, keep in mind that IxD ranges from the paper napkin sketch you made in a hurry at the cafe, to the detailed prototype of the final product that you’ll be showing the design-lead for validation. The tools are not the end-all-be-all of the domain, they are there to just help in the process of conveying; they are after all — tools.

4. Are there any myths that I should not be misguided by?

Like all domains, IxD is no exception to myths and false prevalent statements. It is our duty to carry out myth-buster operations and understand (and remember) the truth. Let’s take a look at some such statements that could not be any more false.

Minimal UI is the ultimate truth in IxD — no it’s not; maniacal addiction to minimalism is more dangerous than beneficial in any way
IxD is a one-time thing — no, it’s not a part of the process; it spans the entire life of the product, right from the inception
Sprinkle some IxD on a product to make it a great success — sounds funny, but clients and PMs with limited knowledge make this assertion
People can tell you what they want — maybe, but not what they need; and that is where extensive research comes into play
Good IxD design is universal — if you have a real understanding of what UX is, you will not make this mistake. Good IxD is context-based, and so its “good”-ness will depend on the product or interface whose IxD is being looked into
UI and UX are the same thing — *sigh*

Alright then! You have acquainted yourself with Interaction Design and now you’re ready to dive into deeper waters. What should you read? What should you follow?

5. Where can I find further resources?

Resources can be found in plenty online, but frankly, there are not many reliable and trustworthy sources. That said, here are some of the best resources you can get your hands on (rather, your mouse pointers on) to get started on the right track.

If you are an avid reader (assuming you are, since you have stuck around till here) here are some of the best reads to feast on.

The Design of Everyday Things — Donald Norman (read this anyway)
Interaction Design — Beyond human-computer interaction
Designing for Interaction: Creating Innovative Applications and Devices — Dan Saffer
Designing for the Digital Age: How to Create Human-Centred Products and Services — Kim Goodwin
Designing Interfaces — Jenifer Tidwell
Interaction Design: Beyond Human-Computer Interaction — Yvonne Rogers
Don’t Make Me Think — Steve Krug

Last but not the least, if you have dived into IxD already, or you’re about to, the Interaction Design checklist would be a great resource to have at hand. This is an exhaustive list of some of the most important points that ideally, you should have checked during the design process. It may not be totally foolproof but professionals have found it to be really good and useful.

And by now, if you are considering delving into the domain of IxD, or maybe if you are just curious — you might be wondering what the future of this discipline looks like.

6. What is the future scope of Interaction design?

Well I do not have a crystal ball in front of me, but I can safely say this — we need to get better, as designers. Because to get the desired future, in the words of Uday Gajendar,

We must learn how to shape conversations, engagements, and embodiments of interaction. A designer who strategically applies such concepts will be best-positioned to define meaningful futures for society and industry.

Interaction design is everywhere people interact with systems and products. So any technological advancement, be it wearables like the Apple Watch or the Google Glass, new experience-forms like AR, VR (even nascent forms — MR and XR) and intangible technologies like BitCoin have an IxD touch to it; and whatever advancement we are to see in the future (more voice-enabled, gesture-enabled et cetera), will definitely be covered under the scope of Interaction design.

If user interaction is a conversation between your user and the product, then your product better participate in a friendly, interesting, and helpful manner.

Make stuff that matters. That should be the war-cry of all designers. Interaction designers shouldn’t be any exception. Of course, our app or product might be a technological masterpiece, yet in the end, it’s the users who have to interact with it. So, the users get to decide if it’s a success or a failure. If we are to become the architects, the builders of the future — IxD can be a very powerful tool in our utility-belt!