The World Wide Web is like a running race or marathon where websites compete to reach the finish line first. In this case the finish line is higher ranking. And in this race for supremacy it is important to avoid duplicate content and its penaltiesTo facilitate the efficient functioning of directories search engines have been armed with content filters. This removes or filters duplicate content from pages it’s indexing. And the most hurtful penalty is lower rankings

Unfortunately, these filters not only catch rogues but web pages that are genuine too. What webmasters need to do is understand how filters function and know what action is to be taken to avoid being filtered out. Websites that feature identical content. And when within a site the webmaster includes many copies or versions of pages to cheat the search engines. Filters are also extremely sensitive to “doorway” pages