Definition:
Doorway pages are web pages created specifically to climb positions in the natural listings of a search engine.
These pages are usually filled with keywords and are meant to funnel visitor traffic to the main website. This practice is generally regarded as an outdated spam tactic and the term should not be confused with a landing page.
Operation of a doorway page
If a user clicks through an open door page on a results page, in most cases they will be directed to another page, by updating the page. Other forms of redirection include using Javascript and server-side redirection, from the server configuration file. Some gateway pages can be dynamic pages generated by programming languages such as Perl and PHP.
Doorway pages are often easy to identify, as they are designed primarily for search engines, not humans. Sometimes an open door page is copied from another high-ranking page, but this is likely to cause the search engine to detect the page as a duplicate and exclude it from search engine lists.
The Doorway pages and the blackhat
Because many search engines penalize for using the update meta command, some open door pages only trick the visitor into poking on a link to take them to the desired landing page or use JavaScript for redirection.
Other more sophisticated open door pages, called Content Rich Doorways, are designed to get the maximum position in search results without using redirection. These incorporate at least a minimal amount of design and navigation similar to the rest of the site to provide a more human and natural-looking look. Visitors are offered standard links as calls to action.
Doorway pages are also typically used for sites that have a blacklist of URLs known to host spam, such as Facebook, Tumblr, and Deviantart.
In any case, using doorway pages in SEO is an absolutely discouraged practice that does not offer any positive results in the medium or long term.
Can a Doorway Page be beneficial?
Unfortunately there are still consultants who claim that the “doorway pages” are the only way to position themselves at the top of Google and recommend buying expensive and useless software to make them faster.
However, all these pages will only create ineffective results in search engines, making the search process even less effective. In addition, these magical software packages demand a lot from you, the user. You have to suggest keywords, key phrases, keyword density, template filling, meta tags, etc.
In the process of search engine optimization, there is no single and easy solution. Every page needs to be optimized for search, which means attracting the search engines you are looking for.