I am not sure if the title of this post is all that clear. Basically, if you go to the Robots.txt informational page at the Wikipedia and scroll down to the Directives within a page it claims Google has has a tag for indicating which "portions of a page that should not be indexed." Keep in mind, Google AdSense has such a tag that enables you to tell Google which content is the most relevant towards the ads you want to display. But Google, as far as I know, does not have a way for you to tell the web search index and bots which parts of your page are most relevant to the user.
Google uses comments for the same purpose: <!--googleoff: index--> ... <!--googleon: index-->
As far as I know, Google doesn't. I even searched for that on Google Help but nothing found.
Hope someone clarifies either at Google or Wikipedia and makes that correction in either place.
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