In terms of functionality and features, both OpenSearch and Elasticsearch offer similar capabilities for search and analytics. OpenSearch is based on the same core technology as Elasticsearch, but it is developed and maintained separately by the OpenSearch community. However, as OpenSearch is a newer project, it may have some differences in terms of features and performance compared to Elasticsearch. The main differences between OpenSearch and Elasticsearch is the development and governance model. OpenSearch is developed and governed by a community of developers who follow a more open and transparent process. Elasticsearch, on the other hand, is developed and maintained by Elastic, a company that also provides commercial products and services based on Elasticsearch. In terms of licensing OpenSearch is under the Apache License 2.0, which is a permissive open-source license that allows for both commercial and non-commercial use. Elasticsearch, on the other hand, is dual-licensed under the Elastic License and the Server Side Public License (SSPL).