To those who are constantly monitoring changes in Google algorithms yet unsure what these updates — named after cute animals — really mean, I hope this short post will give everyone a better understanding.
Panda update refers to algorithmic changes by Google mainly intended to filter pages that are identified as low-quality and bring low value to Google search users. By saying low-quality, Google could mean various things that are associated to uniqueness of content, user experience of those who accessed these pages. The exact list may not be disclosed fully, but Google has always been preaching about making websites as useful to users as possibles. To define such rather subjective criteria, Google relies on factors such as volume of visitors who block the websites on search results, analytics data which lean towards usability.
So, it is safe to say that Panda addresses websites that are not involved in spam but are low in quality (thin or duplicate amount of content) that offer no real value to readers. They may include site scrapers (copying content elsewhere ) or sites that are littered with advertising. But it’s not always a clear cut rule, as bigger websites with established content features like Demand Media and About.com.
While Panda update focused on content, Google’s Penguin update specifically targets web spam, which includes keyword stuffing and link spamming. Typical visitors may not easily notice such violations, especially if the offense centers on acquiring plenty of low-value, irrelevant inbound links. Since Google’s sophistication extends beyond what’s visible on web browser, it becomes easier to pinpoint website that violate Google’s quality guidelines. Over-optimization is also covered under Google Penguin, and includes sites that excessively emphasize the same keyword or phrase as anchor text or usage of keyword-rich domains.
Google’s Panda update is not a penalty but mere fine-tuning of its algorithm in hopes of delivering highly relevant search results. So if we notice drops in traffic due to a Panda update, submission of reconsideration request to restore pre-Panda update ranking will not work. The only way to solve this issue is to act on Google’s longstanding advice: improve content quality for website visitors and not search engines.
On the other hand, Penguin is a penalty update which, if our site is affected adversely (through check on web analytics traffic or receiving Google webmaster notification), reconsideration request can be effective only if 1) we know what violations our website did, 2) we acted on it such as removed the offending links or spammy keywords and 3) we notify Google of our actions. Danny Sullivan offers tips for webmasters on how to recover from a Google Penguin update.