Google’s Penguin 2.1 has impacted a lot of websites as it has gone deeper to look for spam, analyzing internal pages as opposed to just the homepage of websites in the earlier Penguin 1.0 update . The problem being addressed here was unnatural, manipulative inbound link profiles. What makes a bad link profile?

Google focused on links that were from
• Automated link exchanges
• Low quality article submissions
• Artificial blog networks
• Fake Profiles
• Blog Comment Spam
• Site wide Link Spam (Header/Footer Link)
• Artificial Blogrolls
• Network websites
• Link Exchange Site (reciprocal sites)
• Malware Attacked sites
• Paid links and Link farms
• Adult websites
• Irrelevant websites
• Foreign language websites
• Domain expired sites
• Sites with server error
• Poor quality sites
• Links from Class C IP
• Links where the anchor text is overly optimized (i.e., exact-match anchor text)

if you had indulged in buying mass links, spamming low quality directory sites with your links, or comments spamming, there’s a good chance your site was affected by the Penguin 2.1 update.

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