What does this mean?

All images, video, audio and other media should specify appropriate alternative text.

For example:

<img src="apple.png" alt="Apple">

We recommend you read this comprehensive guide to writing alternative text by WebAIM.

The W3C also provide more information on how to satisfy this check in Technique H37.

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How close this website is to fixing this issue.

111 distinct issues were found in the sample of 125 web pages.
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