Understanding the difference between "change of context" and "change of content" is critical for web accessibility. A change of context represents a significant shift in the webpage's structure or navigation, while a change of content is a minor modification within the existing context.
For users who navigate websites with assistive technologies like screen readers or screen magnifiers, a sudden change of context, like a new window popping up unexpectedly, can be incredibly disorienting. Because these tools present information linearly and may not capture the full context of the webpage, users may need help understanding this sudden shift and how to proceed. It's like assembling a puzzle with half the pieces missing and no picture on the box.
This blog will help clarify the distinction between context and content and how they impact users.
What is a Change of Context?
W3C defines changes in context as "major changes that, if made without user awareness, can disorient users who are not able to view the entire page simultaneously."
For example, "opening a new window, moving focus to a different component, going to a new page (including anything that would look to a user as if they had moved to a new page), or significantly re-arranging the content of a page are all examples of changes of context." (On Focus: SC 3.2.1)
Unexpected changes in context can frustrate users and prevent people using assistive technologies from operating a website. For example, if a new window appears without warning while browsing with a screen reader, the user may not understand how to find the content they need.
What is a Change of Content?
Website content is a webpage's text, visual, and aural components. It can be informational, educational, entertaining, or utilitarian. (Techopedia)
A change of content is any minor alteration to the context of a webpage, but it is not always a change of context.
Some examples of content changes that are NOT context changes would be:
- Expanding accordions or menus.
- Updating the text in a product description.
- Changing the active tab in a navigation bar.
- Expanding a dropdown menu to reveal more options.
- Displaying a live update on a data dashboard without changing the page structure or layout.
- Showing or hiding elements based on user interaction. For example, a filter on a job search website.
Essentially, the "what" of the content has changed, not the "where" or "how" the user interacts with it.
When it comes to changes in content, remember:
- An important indicator of a content change that does not constitute a context change is when focus remains on the same element or area of the page.
- Minor visual changes, such as font size, color, or layout tweaks within a page section, are usually considered content changes, not context changes.
Why Does the Distinction Matter?
Understanding the relationship between a webpage's content and its context allows designers and developers to leverage this key difference in creating websites that support users of all abilities.
A sudden, unannounced change of context can impact website understandability. "Understandable" is one of the Four Principles of Accessibility.
"Understandable - Information and the operation of the user interface must be understandable. This means that users must be able to understand the information as well as the operation of the user interface."
Changes in context affect:
- Users with disabilities and assistive technology users:
- Screen readers users may lose their place on the page or become disoriented and unsure of how to correct.
- Users with cognitive disabilities might struggle to understand the change and what to do next.
- Users with mobility impairments might have trouble re-orienting themselves.
- Accessibility compliance: The WCAG addresses the need to manage context changes and provide users with necessary notifications.
- 3.2.1 On Focus (Level A) – A change of context does not automatically occur when an element receives focus.
- 3.2.2 On Input (Level A) – A change of context does not automatically occur when changing an interactive component.
- 3.2.5 Change on Request (Level AAA) – Changes in context are always user-initiated or can be turned off.
- 4.1.3 Status Messages (Level AA) – Status messages can be presented to assistive technologies without receiving focus (i.e., without a change of context).
Protips: Avoid Unexpected Changes in Context
- While changes in content often require minimal notification (e.g., a status message), changes in context usually need to be explicitly communicated to the user beforehand to prevent confusion. For example, you must inform the user if a link opens to a new webpage. This can be accomplished with the "title" attribute in <a href> tag.
- Allow users to control the context changes through buttons or links. For example, provide a button or link on a page with news items that allow the user to update the content.
While content changes are important considerations for clear communication, unexpected changes in context can truly disrupt the user experience and present significant accessibility challenges. Keeping in mind how dynamic elements and transitions impact users with disabilities, you can create digital experiences that are genuinely inclusive and enjoyable for everyone.