Google has released an update to its Penguin algorithm called Penguin 2.0 that aims to crack down on websites using spammy techniques like unauthorized backlinks, duplicate content, and keyword stuffing to improve their search engine rankings. This update has negatively impacted many sites, including some travel, gaming, porn, and educational sites. Matt Cutts warned that Penguin 2.0 seems stricter than previous versions and will more strictly penalize websites using black hat SEO techniques. Google will now more closely inspect websites' content and on-page SEO to determine their true relevance and authority.