Use responsive design to allow your content to zoom and respond to various screen sizes.
Present content without loss of information or functionality, and without requiring scrolling in two dimensions, except for parts of the content which require two-dimensional layout for usage or meaning.
Examples of content which require two-dimensional layout are images, maps, diagrams, video, games, presentations, data tables, and interfaces where it is necessary to keep toolbars in view while manipulating content.
Media player accessibility is essential for video content. Evaluate the accessibility and cross-device compatibility of the media player that comes with your video-distribution platform. Test the player in different platforms and devices to evaluate the user experience it provides out of the box.... Read more about ✎ Technique: Choosing a media player
Some people understand complex information best when it's presented visually, such as as a chart or diagram, while others find that reading the information suits them better. For people who use screen readers, a good text equivalent of the information that’s presented graphically is essential for their understanding.
For simple graphics, providing a succinct, informative text alternative is usually fine. But for complex graphics, it's not enough to provide a screen reader user with only short alternative...
Captions allow people who can't hear a video's soundtrack to have access to a text version of the information provided in the audio.
If you decide to caption your own video content rather than outsource this job to a captioning service, make sure the captions provide an accurate and meaningful alternative to the audio. In particular, when writing captions for audio content in a video, make sure all the spoken content is available in captions, as well as indications of speaker switching (using ">>...
The most appropriate alternative text for an image depends very much on the context of the image in question. You must provide information for that image that takes into account its purpose and also the surrounding text on the page. The same image might need different alternative text depending on how it's used.... Read more about ✎ Technique: Writing alternative text