I am introducing two new terms that comes in SEO.
Cloaking is a term used when webmaster used different pages for Search engine and regular visitors.
Doorway page is page optimized for a phrase useful for search engine and then redirect the users to a different page. The doorway page do not/almost do not have any meaning for normal visitors.
Search engines generally do not like cloaking and doorway pages. Cloaking is acceptable in some cases but doorway pages have no meaning for user and that is penalize when detected by search engine.
Doorway pages are simple and it is clear that it must not be used. No good sites think of it, so it is not interesting to discuss. Cloaking is something debatable. Cloaking is acceptable in some cases for some reason. I am not very sure! Ajax cannot be read by robots. So, if content served through Ajax steps is same the content got through robots then it will be spared. I saw carrentals.com/ is using this kind of cloaking. I also researched on the topic and I feel this is acceptable in some form and for good reason. How search engine will crawl the page accessed through Ajax / Iframe based on user action?
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