... Read more about ✎ Technique: Non-text contrast

Avoid referring to a button, menu, or other item in the page only by its position on the page; instead, use additional information that describes the content.

Referring to a specific item in the page content by only its visual position prevents people who use screen readers from being able to make sense of this visual description. Another downside to referring to items by their position is that their position might change when the page is viewed at different screen sizes, such as on...

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...

Some people with reading difficulties or visual impairments need to customize the display of text to make it easier to read. When text is presented as an image of text, that limits their ability to change the appearance of that text. So wherever possible, use text along with CSS to apply styling (such as color, typeface, or size).

If you use an online content editor to write content, the styling will happen automatically. If you feel that you need text that deviates from the style, formatting options...

Some people with color deficit have trouble differentiating between specific colors, such as between red and green or red and black. Screen reader users do not access content visually, so they do not have access to color information.

Color is a powerful visual means of presenting or distinguishing information, but when you use color to identify or distinguish information, make sure that this information is still available to people who can't perceive color.

Icon fonts are a popular and effective method for providing scalable symbols that can be used to label controls and provide graphical information. The information provided by icons also needs to be available to people who can’t see them.

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

People differ in the way that they can (or like to) consume information, especially in educational contexts. Some people might prefer information provided in text, or video, or audio; and their accessibility needs can also influence their preferences.

But while accessibility for images often focuses on providing a text alternative for screen-reader users, we can also look at the issue from the other way around—providing a graphic alternative for text to make the underlying information or concept easier to...

Each image requires alternative text that is equivalent to the information it conveys, unless the image is purely decorative and provides no useful information. So you need to be careful about what value you give the alt attribute.