Doorway pages are Web pages designed and built specifically to draw search engine visitors to your website. They are standalone pages designed only to act as doorways to your site. Doorway pages are a very bad idea for several reasons, though many SEO firms use them routinely.
Doorway pages are used to work as a bridge between user and your website.Only a content rich doorway page is considers as good otherwise they considers as unethical practice of seo.
Doorway pages are a type of web page created exclusively to gain popularity with a specific search engine. They are also referred to as bridges, gateways, and entry pages. They are a matter of contention within the search-engine optimization world, with some holding that their use is both immoral and ultimately counter-productive, and others believing they are a sure-fire way to achieve consistently high rankings.
Doorway pages are simple HTML pages that are customized to a few particular keywords or phrases, and its programmed to be visible only by specific search engines and their spiders.
Doorway Pages are specifically made to rank well in search engines for particular keywords, serving as an entry point through which visitors pass to the main content.