OpenSearch Distributed

OpenSearch is a distributed search and analytics engine. Data is split into shards (partitions) across multiple nodes (servers). Users query via REST API or dashboards. Queries execute in parallel on all shards, results aggregated. Index (table) with 1B documents takes seconds to search because 1000s of cores search simultaneously. OpenSearch is a fork of Elasticsearch created after Elastic moved to proprietary license. API 70% compatible, but fully open-source.