Elasticsearch is a distributed search and analytics engine built on Apache Lucene. It stores data as JSON documents behind a RESTful API, and new data becomes searchable in near real time, within about one second. It scales horizontally by adding nodes, and it keeps copies of the data on several nodes for reliability.
Its main use cases are:
Full-text search on websites, documents and e-commerce products.
Log analytics on application, system and security logs, often with the ELK stack of Elasticsearch, Logstash and Kibana.
Real-time analytics, such as business metrics and application performance monitoring.
Data aggregation for complex analysis and reporting.
Geospatial search and analytics by location.
You search and analyze the data with the Query DSL, a JSON-based query language.
Rewriting in plainer words…
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