Elasticsearch is a search engine based on Lucene. It provides a distributed, multitenant-capable full-text search engine with an HTTP web interface and schema-free JSON documents. Elasticsearch is developed in Java and is released as open source under the terms of the Apache License. Official clients are available in Java, .NET (C#), Python, Groovy and many other languages. Elasticsearch is the most popular enterprise search engine followed by Apache Solr, also based on Lucene.
It is developed alongside a data collection and log parsing engine called Logstash, and an analytics and visualization platform called Kibana. The three products are designed to be used as an integrated solution, referred to as the "ELK stack".