Cloaking refers to the practice of presenting different content or
URLs to users and search engines. Serving up different results based
on user-agent may cause your site to be perceived as deceptive and
removed from the Google index.
Some examples of cloaking include:
Serving a page of HTML text to search engines, while showing a page of images or Flash to users.
Serving different content to search engines than to users.
If your site contains elements that aren't crawlable by search engines
(such as rich media files other than Flash, JavaScript, or images),
you shouldn't provide cloaked content to search engines. Rather, you
should consider visitors to your site who are unable to view these
elements as well. For instance:
Provide alt text that describes images for visitors with screen readers or images turned off in their browsers.
Provide the textual contents of JavaScript in a noscript tag.
Ensure that you provide the same content in both elements (for
instance, provide the same text in the JavaScript as in the noscript
tag). Including substantially different content in the alternate
element may cause Google to take action on the site. Sneaky JavaScript
redirects
When Googlebot indexes a page containing JavaScript, it will index
that page but it may not follow or index any links hidden in the
JavaScript itself. Use of JavaScript is an entirely legitimate web
practice. However, use of JavaScript with the intent to deceive search
engines is not. For instance, placing different text in JavaScript
than in a noscript tag violates our Webmaster Guidelines because it
displays different content for users (who see the JavaScript-based
text) than for search engines (which see the noscript-based text).
Along those lines, it violates the Webmaster Guidelines to embed a
link in JavaScript that redirects the user to a different page with
the intent to show the user a different page than the search engine
sees. When a redirect link is embedded in JavaScript, the search
engine indexes the original page rather than following the link,
whereas users are taken to the redirect target. Like cloaking, this
practice is deceptive because it displays different content to users
and to Googlebot, and can take a visitor somewhere other than where
they intended to go.
Note that placement of links within JavaScript is alone not deceptive.
When examining JavaScript on your site to ensure your site adheres to
our guidelines, consider the intent.
Keep in mind that since search engines generally can't access the
contents of JavaScript, legitimate links within JavaScript will likely
be inaccessible to them (as well as to visitors without
Javascript-enabled browsers). You might instead keep links outside of
JavaScript or replicate them in a noscript tag. Doorway pages
Doorway pages are typically large sets of poor-quality pages where
each page is optimized for a specific keyword or phrase. In many
cases, doorway pages are written to rank for a particular phrase and
then funnel users to a single destination.
Whether deployed across many domains or established within one domain,
doorway pages tend to frustrate users, and are in violation of our
Webmaster Guidelines.
Google's aim is to give our users the most valuable and relevant
search results. Therefore, we frown on practices that are designed to
manipulate search engines and deceive users by directing them to sites
other than the ones they selected, and that provide content solely for
the benefit of search engines. Google may take action on doorway sites
and other sites making use of these deceptive practice, including
removing these sites from the Google index.
If your site has been removed from our search results, review our
Webmaster Guidelines for more information. Once you've made your
changes and are confident that your site no longer violates our
guidelines, submit your site for reconsideration.
