Because search engines operate in a highly automated fashion, webmasters can often use tactics and methods that are not recognized by the search engines to boost rankings. These methods often go unnoticed unless a search engine employee visits the site and notices unusual activity, or a small change in the ranking algorithm causes the site to lose the high rankings it once had. Sometimes companies hire optimization consultants to evaluate competitors' sites and report "unethical" optimization methods to the search engines.
When these spam indexes are discovered, the search engine may take action against those found to be using unethical optimization practices. In February 2006, Google removed the BMW Germany site and the Ricoh Germany site for using these methods.
Cloaking
Usually refers to the webmaster using two different versions of the web page to achieve the optimization effect. One version is only provided to search engines, and the other version is provided to ordinary users. Search engines consider this practice to be normal. If found, the website will be permanently removed from the search engine list. However, for dynamic web pages written by AJAX, Google has also proposed a method called HTML Snapshot to facilitate search engine inclusion.
This is another way to deceive search whatsapp database engines. Usually it means setting the color of the keyword to be the same as the background color of the web page, or using CSS hidden attributes to achieve optimization effects. Once this practice is discovered by Google, the website will be removed from Google's database.
Doorway pages
Also called doorway pages, they are usually generated by software with a large number of web pages containing keywords, and then automatically redirected to the home page from these web pages. The purpose is to hope that these bridge pages with different keywords as targets will get good rankings in search engines. When users click on the search results, they will automatically be redirected to the home page. Sometimes a link to the home page is placed on the bridge page instead of automatically redirecting to the home page.