Doorway - a site created to redirect users to another site. Doorways can be conditionally divided into two categories: White doorways - generally normal sites, sometimes even with unique author's content. good design, etc. But despite the good disguise, the main purpose of the site remains the same - external links to take the user to the main, another site. Black doorway - sites created solely to redirect the user to another site. Having entered such a doorway, the user will immediately be redirected to another site using a redirect. Search engines are actively fighting doorways, and this method of promotion in SEO is no longer effective.