RankBrain uses vectors, which to quote the previous article are "Large amounts of written language embedded in mathematical entities" and tries to understand not only the keywords on a page, but also the intent behind the keywords entered.That's all Google says and there are probably only a handful of people at Google who know a lot more than that, therefore the rest of this article heads down the less traveled path of wild speculation. If you don't know How to optimize for Google RankBrain? Click the follow link.