22.10.2 Providing alternate text for a hotspot in an image map
You specify alternate text for an image-map hotspot via an attribute of the hotspot <area> tag. The alternate text relates to the hotspot link destination. Unlike alternate text for the <img> tag, you cannot specify alternate text for the <area> tag with a marker or a paragraph format. And you might want to use the title attribute of the <area> tag instead of the alt attribute.
§22.10.2.1 Assigning alternate text to an image-map hotspot
§22.10.2.2 Using the title attribute for alternate text for a hotspot
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