How blind people use a computer?
For using computers, blind person use software called “screen readers”. Screen readers convert the text on the web page into spoken words. Blind people listen to web pages through speaker or headphones.
Design Considerations for Web Developers/Designers:
1 Alt text for images
Screen readers cannot read anything if a graphic is without alt text, but if web developer provides alt text with images, screen readers can read information that you provide with alt attributes.
2 Keyboard functionalities
All functionalities must be accessible using only the keyboard (Note: test them with the screen reader, because there are subtle changes in keyboard functionality when the screen reader is on).
3 Good symantic structures
The content must have good structure and semantics, for instance headings, landmarks, tables, lists, etc.). Blind users often pull up lists of headings, landmarks, and other semantic elements to help them understand what is on the page with the help of their screen reader. They can easily navigate by these elements (e.g., jump directly to the main content landmark or to a specific heading).
4 Labeled custom controls
All custom controls like expand/collapse buttons, media player volume control, dialogs, etc., must have the appropriate name/label. And it can be achieved by “Aria”.
Screen readers can’t tell users what the widget is and can’t update users on the properties of the widget unless you supply that information via ARIA names, roles, states, and properties.
5 widgets and live updates and errors must be notify
Blind users must receive instant feedback after all actions, via their screen reader. Silence after starting a feature is always bad! For example: Expanded/collapse region, value changed on a control (e.g., on a slider, successful/unsuccessful form submission, notification that a new “page” has loaded in single-page applications, etc.).
6 Video captions must be there
Videos need audio descriptions. If the video’s dialog, sounds, narration) does not convey everything to a blind person, they would need to know to understand the video. Blind users can hear the dialog, narration, and other sounds in videos, but they can’t see the visual parts of a video. So, if the scenes convey important information, those parts will need to be described out loud for blind users to understand them.