Elasticsearch is a highly scalable search and analytics engine that is used to store, search, and analyze large volumes of data in real-time. It is built on top of Apache Lucene, a powerful open-source search library. Elasticsearch is designed to be distributed, meaning data can be spread across multiple nodes or servers, making it highly available and fault-tolerant.
Elasticsearch is commonly used for a wide range of use cases, including log analysis, text search, business analytics, and more. It supports a variety of data types, including structured and unstructured data, and provides a powerful query DSL (domain-specific language) that allows users to search and filter data with ease. Elasticsearch also offers a variety of features, including aggregation, data visualization, and full-text search capabilities. It can be used as a standalone search engine or integrated with other technologies, such as Kibana, Logstash, and Beats, to form the ELK stack, which is commonly used for log analysis and monitoring.