Since it’s original emergence in 2015, RankBrain has appeared multiple times within SEO news and has become a significant consideration in the world of SEO. Recently, Google announced that RankBrain had become Google’s third-biggest ranking signal, meaning it has now become even more important than ever before.
Previously Google has always been tightlipped about its algorithms and their updates, so for Google to make this claim about the importance of RankBrain, it’s definitely worth taking note.