Postel’s Law in UX Design

Postel’s Law is a crucial law that we all as designers must consider when building accessible and usable products. Postel’s Law also popularly known as the robustness principle is a UX Design principle formulated by an American IT scientist named John Postel. Postel’s Law is important for designers since it touches on one of the most crucial parts of the design ideology which is accepting and implementing feedback. In this article we will discuss what Postel’s Law is? what are the Key takeaways of Postel’s Law? And what are its applications?

Postel’s Law in UX Design

What is Postel’s Law?

Postel’s Law also popularly known as the robustness principle is a UX Design principle formulated by an American IT scientist named John Postel. Postel’s Law states that – “be conservative in what you do, be liberal in what you accept from others”. In simpler terms, Postel’s Law states that when we are actually designing products, applications, or websites we as designers should make sure that the application or website is accessible to most users and we should also allow them to enter or give feedback to us or interact with us in different ways.

The law was formulated by Jon Postel with regard to TCP and networks. It was about creating programs that send messages following a strict set pattern and creating programs that can accept different types of inputs when they are receiving them. And for UX design, this law changed a bit into designing products, applications, or websites that can be accessible by most, and expect different types of responses from users.

Key Takeaways from Postel’s Law

The four key takeaways from the Postel’s Law that you can directly use in your next design project are as following:

1. Empathy is the key: Be empathetic to, flexible about, and tolerant of any of the various actions the user could take or any input they might provide.
2. Accessibility: Anticipate virtually anything in terms of input, access, and capability while providing a reliable and accessible interface.
3. Accept variable input: Accept variable input from users, translating that input to meet your requirements, defining boundaries for input, and providing clear feedback to the user.
4. Always plan before designing: Irrespective of the scale of your project make sure that you at least have a rough plan for your design. The more you can anticipate and plan for in design, the more resilient the design will be.

Application of Postel’s Law

Accessible Design

• The most important application of Postel’s Law is helping the designer in achieving a Accessible Design. Postel’s Law talks about making the product accessible through different types of impairments like vision impairment, sound impairments. Other than this, one can also allow users to interact with the product not only just using the mouse but also have keyboard interaction.

User Feedback

• Postel’s Law talks about being generous when accepting feedback for your application or website. Feedback here not only refers to the feedback we get from the users about our application but also the input values such as “name”, “email id” etc. we have to avoid bringing up errors if that error can be avoided while taking such inputs.

Forms

• Postel’s Law finds an application in designing forms where we can only ask for what’s absolutely necessary. If as a designer you are asking the user for a lot of information unless it is really necessary, this puts a lot of cognitive load on the user and then user’s ability to actually go through the whole form is deteriorated.

Progressive Enhancement

• Progressive enhancement is similar to responsive design but it is a design that actually starts from the mobile device and then goes up on larger devices. A lot of designers work with graceful degradation, in terms of responsive design graceful degradation is building for a wider screen and then try to narrow it down to tablets and then mobile devices. But while we designers work on our desktops, most of our users don’t

Design Systems

• When creating design systems, Postel’s Law tells us to be liberal in terms of the feedback we are getting from the design team from or the content team or from the developers. And we also have to focus on the business strategy and the goals of the business. We can be very liberal when accepting all of that feedback, accepting all of that is definitely going to be part of the process but we also have to be conservative in the output.

Conclusion

Postel’s Law also popularly known as the robustness principle is a UX Design principle formulated by an American IT scientist named John Postel. Postel’s Law states that – “be conservative in what you do, be liberal in what you accept from others”. Postel’s Law is a great way for any designer to have a strict practice of accepting feedback and delivering a consistent feedback. While designing, one make forget these key concepts and that is where including this lay in your design workflow might help you in providing consistent design to your clients. Make sure to follow the points we mentioned in this article in order to follow the Postel’s law and see the improved results in your next design project.