Elasticsearch is a powerful real-time, distributed, open source search and analytics engine built on top of Apache Lucene, a schema-free and developer-friendly RESTful API. Amazon Elasticsearch Service is a managed service that makes it easy to set up, operate, and scale Elasticsearch clusters in the cloud. It comes with built-in Kibana and Logstash plugins.

You can modify clusters with no downtime, and it can be integrated with many AWS services including CloudWatch, Lambda, DynamoDB, and so on. It supports the Elasticsearch API and is a drop-in replacement for your existing Elasticsearch clusters. In addition, you only pay for what you use. It provides simple interfaces for cluster creation and configuration management. These clusters are self-healing clusters, HA (clusters are AZ aware and can spread to multiple AZs), and have high data durability.

Compared with Lucene and Elasticsearch company's offering, Amazon Elasticsearch is a managed service that provides out of the box integration with Amazon Kinesis and S3. However, note that Amazon's version is typically a release behind the official Elasticsearch release, so it may not have the latest features available.