role="presentation" or aria-hidden="true" for decorative images?

Question

Which is semantically better, alt="", role="presentation", CSS bg image or aria-hidden="true" for hiding decorative images from assistive technologies?

Answer 1

The best thing is to use blank alt text.

<img src="squiggle.gif" width="20" height="20" alt="" />

Using null alt text and no title attribute on img elements for images that AT (Assistive Technology) should ignore.

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