Why Penguin 2.1 AND Penguin 5?

If us talking about Penguin 5 in reference to something Google is calling Penguin 2.1 hurts your head, believe us, it hurts ours, too. But you can pin that blame back on Google. Here’s why.

When Google started releasing its “Panda” algorithm designed to fight low-quality content, it called the first one simply “Panda.” So when the second came out, people referred to that as “Panda 2.” When the third came out, people called that Panda 3 — causing Google to say that the third release, because it was relatively minor, really only should be called Panda 2.1 — the “point” being used to indicate how much a minor change it was.
Google eventually — and belatedly — indicated that a Panda 3 release happened, causing the numbering to move into Panda 3.0, Panda 3.1 and so on until there had been so many “minor” updates that we having to resort to going further out in decimal places to things like Panda 3.92.
That caused us here at Search Engine Land to decide it would be easier all around if we just numbered any confirmed update sequentially, in order of when they came. No matter how “big” or “small” an update might be, we’d just give it the next number on the list: Penguin 1, Penguin 2, Penguin 3 and so on.
What Is Penguin Again? And How Do I Deal With It? For those new to the whole “Penguin” concept, Penguin is a part of Google’s overall search algorithm that periodically looks for sites that are deemed to be spamming Google’s search results but somehow still ranking well. In particular, it goes after sites that may have purchased paid links.
If you were hit by Penguin, you’ll likely know if you see a marked drop in traffic that begins today or tomorrow. To recover, you’ll need to do things like disavow bad links or manually have those removed. Filing a reconsideration request doesn’t help, because Penguin is an automated process. Until it sees that what it considers to be bad has been removed, you don’t recover.
If you were previously hit by Penguin and have taken actions hopefully meant to fix that, today and tomorrow are the days to watch. If you see an improvement in traffic, that’s a sign that you’ve escaped Penguin.
Original Source from : http://searchengineland.com/penguin-2-1-and-5-live-173632