What is a "canonical tag"?

A canonical tag is an HTML element specifically designed to address the issue of duplicate content on websites. It achieves this by allowing a webmaster to indicate the preferred version of a webpage when multiple versions of similar content exist. This is important because search engines strive to provide users with the best results, and having different URLs with the same or very similar content can confuse search engines and dilute the ranking potential of each URL.

By implementing a canonical tag, the webmaster effectively communicates to search engines which version of the URL should be treated as the authoritative source for indexing and ranking purposes. This not only helps improve SEO performance but also ensures that the traffic and link equity associated with that content are consolidated to the preferred URL.

In contrast, the other options describe unrelated functions. Organizing webpage layout involves different HTML elements, image compression pertains to reducing file sizes, and social sharing buttons serve a distinct purpose in enhancing user engagement. Thus, the canonical tag stands out as a vital tool for maintaining content integrity and optimizing search visibility.