Apache Cassandra is an open source distributed database management system. It is designed to handle very large amounts of data spread out across many commodity servers while providing a highly available service with no single point of failure. It is a NoSQL solution.
Apache Cassandra is a highly scalable, eventually consistent, distributed, structured row/column store. Cassandra brings together the distributed systems technologies from Dynamo and the data model from Google's bigtable. Like dynamo, Cassandra is eventually consistent. Like BigTable, Cassandra provides a ColumnFamily-based data model richer than typical key/value systems.
Cassandra's Dynamo-based cluster model provides linear scalability and fault tolerance on commodity hardware or cloud infrastructure. Its support for replicating across multiple data centers is best-in-class, providing low latency and the ability to survive entire data center outages.
Cassandra's data model offers the convenience of column indexes with the performance of log-structured updates and powerful built-in caching with the fastest write performance as compared to other database solutions and makes it a compelling option for big data processing. It provides linear scalability with the provision to add/remove nodes on the fly without downtime.
Cassandra was open-sourced by Facebook in 2008 and quickly became a top-level Apache project. Today, it's widely used by companies in many markets.
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