Part 2: Interaction Design principles

The psychological underpinnings and general rules of interaction design. Learn the reasons why designs are built the way they are.

This is fundamental information that sets the scene for all of the other design work you’ll do. Even if you’re considering a research path rather than a design path, you need this information in order to be able to describe why a design may not be working and how it could be improved. 


Learn how to apply simple design principles to web sites and other interfaces. These basic principles are the foundation for all interfaces.

The psychological reasons why good UI design works. These cognitive, perception, and physical concepts will let you see why people behave they way they do, so that you can build websites and apps that work the way your users think.

Course: UX Foundations: Accessibility

UX Foundations: Accessibility

(Derek Featherstone)

​In order to ensure you are making your content available to all of your users, you need to consider accessibility and inclusive design. This​ course shows you how easy it is to lower the barrier to entry, by providing equal access and opportunity to people with a diverse range of hearing, movement, sight, and cognitive abilities.


Course: Universal Principles of Design

Universal Principles of Design

(William Lidwell & Jill Butler)

Based on their book, William and Jill have created a series of 50 (yes, 50!) short sessions on different design principles. Dip in and out at your leisure. This series is completely optional for the course, but the entertaining anecdotes and real-world examples will help you remember a lot of useful concepts.


Choose a popular site or app that you use regularly. List the interaction design principles that you can see being used in it. Think about why the designers chose to use this approach – what other design might have worked instead? 

Discussion topics

If you’ve created a study group, share your homework and the principles you thing most guided the design decisions. For each site or app, discuss what the real-world constraints might have been on the design, and how those influenced it. For instance, you may think there’s a different, better design solution. Why might the product designers have chosen the route they did? (For more on constraints, see this episode


Watch the video from the UX Insights Weekly course on performing a Cognitive Walkthrough. Download the handout.

Now perform a Cognitive Walkthrough for an interaction flow on the site you’ve chosen for your project. An interaction flow is any user task, such as finding an item on the site, buying an item (checkout), signing up for an account, and so on.

Note down areas of concern. Use what you learned from the two core courses to decide what might constitute an issue.

One common way to write this type of information up is to paste each screen in the flow into a presentation deck and use call-outs to show where each issue is that you found.

This presentation deck is the first piece of work that you will add to your portfolio later – congratulations!

Next – Part 3: User Research