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Provide Descriptive Headings and Labels
General Guidelines
Help users understand what information is contained in Web pages and how that information is organized by providing descriptive headings.
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Labels and headings do not need to be lengthy. A word, or even a single character, may suffice if it provides an appropriate cue to finding and navigating content.
Screen Reader Guidelines
Screen reader users frequently navigate web pages by heading structure. These users can pull up a list of all the headings on a page to get a quick overview of the type of content that is available.
This requires headings to be descriptive enough so that screen reader users can quickly get an overview of the type of content that is available on the page.
Lists
HTML lists - <ul>, <ol>, and <dl> - also convey a hierarchical content structure.
Lists should be used to display actual list items. They should not be used for layout purposes.