Hypothetically both store data objects that have key-value pair, and allow querying that body of objects. But both come from 2 different camps and are made for different purposes. MongoDB is a general purpose database, Elasticsearch is a distributed text search engine backed by Lucene. ElasticSearch is very good for specific task — indexing and searching big datasets. It is used when you have some secondary info about your data and you need to know actual records to select. And since it’s architecture is optimized for this, it’s weaker in some other use cases. For example, in compare to many NoSQL databases ElasticSearch is slow on adding new data. In…