[manigandham]

Elasticsearch is a search engine built on Apache Lucene and basically makes it much more usable. It's similar to Apache Solr but easier to get up and running.

It's good at text but can be used as a similarity search system, so you can index and find similar images, audio waveforms, binary data, etc.

Over the years, search queries have become useful for log analytics and so the ELK stack has been developed to become a single solution to do both text search as well as ingest logs and run all kinds of queries, aggregations, and even machine learning.

I think that's what fundamentally hurts it as they are very separate use-cases trying to be served by the same system. We still use ES for search but wish it just focused on that with much better performance, reliable clustering and proper transactions instead.