A Google algorithm update focused on analyzing the quality of links pointing to a site, or more accurately, the overall quality of a site’s backlink profile. First announced on April 2012 and updated periodically after this release, similar to Google Panda. This algorithm targeted so-called “black-hat SEO” tactics which manipulated search rankings by creating links to sites in an unnatural manner. Google analyzes all of the pages which link to a specific site and determine whether the links are a benefit to users, or if they simply serve to manipulate search rankings and adjust the site’s standing accordingly. Google estimates that Penguin affects 3.1% of all searches in English, a relatively large number for one algorithm.