What is the Penguin 3.1 Recovery Algorithm?
 

I have seen today that there are lots of sites get back to their position in Google. What has actually happened? I have seen somewhere penguin 3.1 has been rolled out and many sites getting their position back, is it true? But one of my site does not get back to it's position yet though we have removed all unnatural links.

Well the algorithm has brought on specific sites to recover better positions in the positioning. It predominantly differs with sites since it channels the low quality connection display in the site.