Postels law, also known as the "Robustness principle" originally comes from the development and ideas of how the internet should be designed. The TCP (Transmission Control Protocol) was designed with the following sentence as a central point "be conservative in what you do, be liberal in what you accept from others".
How is this related to design you might ask? Well, really simple, because this can be directly applied to how you should think about design. Think about an input field and how it should be conservative in what it shows.
There should be a field, there should be a small explanation on what is expected in the field (email), and an example in the field helping the user (example@email.com) This should make sure that the user have a clear understanding of what is expected, and the context of the situation. However, once the user starts using it, the input field should accept that the user might make some mistakes. This could be the situation where the user is copy/pasting the email from another loaction, and there is a space at the end of the email. There is no emails that end with a space, (or starts with a space) but instead of just throwing an error in the direction of the user, we should silently understand that the space is not a valid charater and remove it, and handle the situation without bothering the user.
And this does not only apply to UI design, which is often used as an example on where to use this, but also when you are working with UX.
Here we are back to the basics that we talked about in the episode "What is Design" where we talked about the importance of understanding that the actor (our user) makes decisions in an environment (the context) and that we have to design our solution (object) in a way that caters for that. In the end, we know what we want the user to do, but we accept that there is a high chance that they will do something different (and something that could be considered an error) and we have to help them recover from these actions.
Give this episode a listen, its good !
You will learn
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