[_tom_]

You need to do a lot more learning about this subject.

BM25 scores documents based on their contents.

PageRank scores documents based on their sources.

Very different.

If you are starting now, you start with Elasticsearch, because you can't start with PageRank and all the thousands of other things that make up what you think of as Google Search.

If you have years, people and billions of dollars, you can start building towards google-like capabilities. Elasticsearch allows you to add capabilities like google provides, but you still have to build them.

Build your first round of search on Elasticsearch, and you'll likely learn enough to start understanding the difference between the two.

[donboscow]

I am aware that I need more learning, no need for that advice. I also know that BM25 and PageRank are different, were they the same, there wouldn't have been a need for two of them, my question was ver clear - which one in the long run yields better (in terms of relevance) search results comparatively. I am also aware that ES is a starter pack and Google is a beast that will need much much more than just an ES stack, what i wanted to know was - whether ES offers the capabilities to fine tune it to make it behave like such a beast. Thank you for your advice, but it is better if you read the question first before lecturing others in a condescending manner.