Adding an Alternate Text or Alt Tag to images is the first principal of web accessibility.
Alternate Text or Alt Tag is a word or phase that is inserted as an alternate attribute in the webpage to describe an image to those who can not see the image, it provide a clear text alternative of the image for screen reader users. Alt Tag serves several functions
- It is read by screen readers in place of images, allowing the content and function of the image to be accessible thru the screen reader
- It is displayed in place of the image in the browser if the image file is not loaded or when the user has chosen not to view the image
- It provides a semantic meaning and description to images which can be read by search engines
Every image MUST have an Alt Tag unless it is a decorative image or when the content presented in the image is conveyed elsewhere, such as in a caption.
When inserting photos to your website, always include a description of the image in the "Alternative Text:" field.
