• MongoDB - a very popular, cross-platform, document-oriented database.
• Elasticsearch - a distributed REST-style search engine designed for cloud computing.
• Cassandra - an open source distributed database management system. Originally designed and developed by Facebook, it is deployed on a large number of commodity servers to process large amounts of data. High availability, no single point of failure.
• Redis - open source (BSD) in-memory data structure store, memory repository, cache, message broker.
• Hazelcast - Java based in-memory data grid.
• EHCache - Widely used open source Java distributed cache, J2ee, lightweight container.
• Hadoop - an open source distributed big data framework developed in java to process very large-scale data. Hadoop is a clustered deployment.
• Solr - Open source enterprise search platform developed in java. Originally ascribed to the Apache Lucene project.
• Spark - the most active project in ASF, is an open source cluster computing framework.
• Memcached – a general-purpose distributed cache system.
• Apache Hive - supports SQL-like encapsulation in Hadoop, turning SQL statements into mr programs for execution.
• Apache Kafka – a high-throughput, distributed, message publish-subscribe system, originally developed by Linkin.
• Akka– Developed in Java to build high-concurrency, jvm-based elastic message-driven applications.
• Hbase - An open source distributed non-relational database based on Google's BigTable paper. The development language is Java, and HDFS is used as the underlying storage.
• Neo4j – an open source graph database implemented in Java.
• CouchBase – An open source distributed NoSQL database for Document, optimized for interactive applications.
• Apache Storm – an open source distributed real-time computing system.
• CouchDB – Open source document-oriented NoSQL database using json to store data.
• Oracle Coherence – an in-memory data grid solution that enables enterprises to predict the scale of mission-critical applications by providing fast access to hot data.
• Titan – A scalable graph database optimized for cluster storage and querying hundreds of billions of graph data.
• Amazon DynamoDB – a fast, flexible NoSQL database that can handle the needs of applications of all sizes, including persistence, millisecond latency.
• Amazon Kinesis – a real-time data computing platform on AWS.
• Datomic – provides full transaction support, cloud computing, distributed database, and Clojure for development language.