Accessibility Vocabulary Check: POUR?

illustration of two people back to back using tablet and screen reader software on a laptop

Pour is an acronym that the WCAG uses to describe accessibility. Each letter stands for one of the four principles of content accessibility. These principles break down important considerations for ensuring that content, web or otherwise, is accessible to as wide an audience as possible. This blog will break down each letter of POUR to help us better understand these principles. 


The perceivable principle refers to users’ ability to perceive content.  And it refers specifically to making content perceivable to multiple senses. If, for example, there is content relevant to the context of your site or document that is only presented in the form of audio, then users who cannot perceive audio content are not able to perceive your message. On the other hand, adding alt text to an image is an example of making visual content perceivable by other means. 


For a site to be Operable, its controls and interface must allow users to browse its content.  However, different people have their own methods of browsing content and websites. The Operable principle refers to making sure that each of these methods are viable. For example, some users browse the web using Keyboard Navigation. If a site is not properly configured for this, those users are excluded.


When you click a button on a well designed site or web application, it is very clear that something has happened.  A success message may flash or the button itself may change color or shape as it is submitted. If you clicked on the button and nothing happened, it would be difficult to understand what the button’s purpose was. If there were text content that was too small or didn’t have sufficient contrast for you to read, it would be similarly difficult to understand its purpose. 


Some users will access content on assistive devices, such as screen readers.  For content to be Robust, it must be optimized to function properly on these assistive devices. This often means using good HTML practices and including ARIA where applicable.  

Accessibility Vocabulary Check: POUR?
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