Google Penguin

Google Penguin is a codename for a Google algorithm update that was first announced on April 24, 2012. The update is aimed at decreasing search engine rankings of websites that violate Google's Webmaster Guidelines by using now declared black-hat SEO techniques involved in increasing artificially the ranking of a webpage by manipulating the number of links pointing to the page. Such tactics are commonly described as link schemes. According to Google's John Mueller, Google has announced all updates to the Penguin filter to the public.

By Google's estimates, Penguin affects approximately 3.1% of search queries in English, about 3% of queries in languages like German, Chinese, and Arabic, and an even bigger percentage of them in "highly spammed" languages. On May 25, 2012, Google unveiled another Penguin update, called Penguin 1.1. This update, according to Matt Cutts, head of webspam at Google, was supposed to affect less than one-tenth of a percent of English searches. The guiding principle for the update was to penalize websites using manipulative techniques to achieve high rankings. Pre-Penguin sites commonly used negative link building techniques to rank highly and get traffic, once Penguin was rolled out it meant that content was key and those with great content would be recognised and those with little or spammy content would be penalised and receive no ranking benefits. The purpose per Google was to catch excessive spammers. Allegedly, few websites lost search rankings on Google for specific keywords during the Panda and Penguin rollouts. Google specifically mentions that doorway pages, which are only built to attract search engine traffic, are against their webmaster guidelines....

In January 2012, the so-called Page Layout Algorithm Update (also known as the Top Heavy Update) was released, which targeted websites with too many ads, or too little content above the fold.

Penguin 3 was released October 5, 2012 and affected 0.3% of queries. Penguin 4 (also known as Penguin 2.0) was released on May 22, 2013 and affected 2.3% of queries. Penguin 5 (also known as Penguin 2.1) was released on October 4, 2013, affected around 1% of queries, and has been the most recent of the Google Penguin algorithm updates.

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