Overview of alt text

Credit for the following goes to  https://webaim.org/techniques/alttext/

• Adding alternative text to images is one of the easiest accessibility principles to learn and one of the hardest to master.
• Alternative text may be provided in the alt attribute or in the surrounding context of the image.
• Every image must have an alt attribute.
• Alternative text should:
  • present the CONTENT and FUNCTION of the image.
  • be succinct.
• Alternative text should not:
  • be redundant (be the same as adjacent or body text).
  • use the phrases "image of…" or "graphic of…".
• Appropriate alternative text depends heavily on the image's context.
• Alt text of a functional image (e.g., an image within a link) should describe the function as well as the content.
• Decorative images still need an alt attribute, but it should be null (alt="").

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1. Click the image to display the image properties menu.
   
2. Click the Properties button.
3. The Image Properties dialog box appears.
   

4. Enter alt text in the Alt text field. Do not add text in the Title text field.

Add alt text in the XHTML

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