IMG ALT recommendations - tabular summary Summary ALT text recommendations, and notes on viewing situation. The ALT text provides alternative or substitute text, for use when the image is not being displayed. The advice here is offered as a good compromise that works in all three types of viewing situation, with notes on the consequences for the different types.
Reader is unlikely to want to view the image.
Don't rely solely on image shape or colour to convey significant information content. If possible, arrange it so there will be no more than one anchor per displayed line. You may want to mention the image file size, if it's substantial. Don't frustrate the reader by claiming that they must load this image. Some of the earlier compromises, in which the ALT text was trying to do duty for a number of competing purposes, can be avoided by exploiting those attributes to provide the relevant accessibility features, leaving ALT to do the job for which it was intended, i.e alternative text.