Apache Cassandra is an open-source, NoSQL, wide column data store that can quickly ingest and process massive amounts of data. It’s also decentralized, distributed, scalable, highly available, fault-tolerant, and tunably consistent, with identical nodes clustered together to eliminate single points of failure and bottlenecks (we’ll go over each of those terms later). You can deploy Cassandra on-premise, in the cloud, or in a hybrid data environment.

More info http://cassandra.apache.org/