For each seo optimization, this is the hardest algorithm on google. This is that part of the analysis of your links that tries to find out how many of the links pointing to your site are "faulty" and "inappropriate" sites. It determines whether these links are naturally placed in forums, blogs and articles in reputable news portals, etc ..
Because of Penguin, algorithms sites with inappropriate links go back in the ranking on Google. It is therefore very important not to trust anyone who offers you "submit" (publishing your site to web directories). Proper optimization requires links from relevant sources that are authoritative. The algorithm monitors the distribution of links, whether they are directed to only one page on your site or scattered to different pages. Naturally placed links are distributed to different pages of your website. That means, the analysis clarifies what "Ankors" (words in the links) are used to determine whether they are placed purposefully to help qualify a certain phrase or word.
This algorithm is perfected and improved constantly by Google. This is one of the main reasons, results in the ranking to change over the time.
The Viking monitor trends Penguin algorithm and aims to be in sync with them.
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