The ADA’s relationship with websites has been a complicated and often confusing story. The ADA does not explicitly address online compliance, even after undergoing several amendments in the far more web-oriented era of 2008. With no specific coverage under the law, it usually falls to the courts to determine how ADA standards apply to websites—or whether they do at all.
The words in the tag should be more than a description. They should provide a text equivalent of the image. In other words, the tag should include the same meaningful information that other users obtain by looking at the image. In the example of the mayor’s picture, adding an “alt” tag with the words “Photograph of Mayor Jane Smith” provides a meaningful description.