In a nutshell, the Google Panda update (originally referred to as the Farmer Update) was an algorithmic change to Google search engine which decreases the ranking of websites that have duplicate content and use poor quality link building methods.
While many SEO’ers were pulling out there hair on Feb. 23rd since it targeted a few practices that many of them used…
One focus of the Panda Update is to decrease the ranks of those who scraped and duplicated content from the web on their own sites. Prior to this update, you’d often get duplicated articles from low ranking directories showing on the first page of many searches, but now they’ve been Panda’d. Many e-commerce sites were also penalized as a result of the duplicated content since a lot of them use the same item descriptions as other sites selling the same products.
High Ad Volume
Another aspect of the Panda Update decreases the rank of websites which feature too many ads. This is an interesting one since google’s adsense network was likely the supplier of many of those ads, but regardless if your site had huge chunks of ads and little content, then you got panda’d.
Poor Link Building Techniques
Finally, the Panda update also went after sites with poor link building activities. If you were mass posting the same articles all over with the same anchor text, or buying a lot of links then your site was likely Panda’d. You might think that this would only effect work at home SEO’ers however many of these mass linking and 3 tier linking methods had become commonly used by even some of the largest SEO firms. Large companies such as J.C. Penney’s received a temporary ban because of their linking practices (theirs lasted about 5 months).
In the end I’m happy the Panda update was released. It was becoming a bit too easy to get high rankings without quality content but this has brought us one step closer to relatively spam free search results and it benefits the SEO companies providing quality services