What is doorway page?

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.

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Originally Posted by seairexim

I read someone posted, doorway page is a black hat SEO techniques. Can I have details about the doorway pages. What we meant by doorway page?

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Doorway pages are typically large sets of poor-quality pages where each page is optimized for a specific keyword or phrase