Google panda is the Google's new algorithm which aims to detect the site which having copied content and penalized them. Many of the sites has lost their rankings because of the copied content but it remain a blessing for the unique content holders.
Google Panda refers to the changes introduced in 2011 to the search algorithm used by Google to improve Internet search results. The change aims to lower the rank of "low-quality sites" in search results and return high-quality sites to Google's users.
If you feel like you’ve been unjustifiably hit by the Google Panda Update, Google recommends that you let them know in this forum thread. For other resources, that may help you, we recently created this Delicious stack of Panda resources (which by the way is still a work in progress. Feel free to share other resources you think would be helpful, and we’ll consider adding them).
* Read More About Google Panda Update on Wikipedia
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