Google Algorithm Change History

Each year, Google changes its search algorithm around 500–600 times. While most of these changes are minor, Google occasionally rolls out a “major” algorithmic update (such as Google Panda and Google Penguin) that affects search results in significant ways.

For search marketers, knowing the dates of these Google updates can help explain changes in rankings and organic website traffic and ultimately improve search engine optimization. Below, we’ve listed the major algorithmic changes that have had the biggest impact on search.

2015 Updates

RankBrain* — October 26, 2015

Google made a major announcement, revealing that machine learning had been a part of the algorithm for months, contributing to the 3rd most influential ranking factor. *Note: This is an announcement date - we believe the actual launch was closer to spring 2015.

Google Turning Its Lucrative Web Search Over to AI Machines (Bloomberg)

FAQ: All About The New Google RankBrain Algorithm (SEL)

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resources: https://www.moz.com