Doorways are sites or pages created to rank highly for specific search queries. These may serve as intermediate pages to real information - designed to increase the search footprint, they eventually take the visitor essentially the same destination (ref. https://support.google.com/webmasters/a ... 1311?hl=en)
eg:
-Having multiple domain names or pages targeted at specific regions or cities that funnel users to one page
-Pages generated to funnel visitors into the actual usable or relevant portion of your site(s)
-Substantially similar pages that are closer to search results than a clearly defined, browseable hierarchy
Google does not want to rank such pages and hence is taking more strict action against these. Read more on
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