Cassandra

Apache Cassandra is an open-source, distributed NoSQL database designed for linear scalability and high availability across multiple data centers.

Engineered at Facebook and proven at scale by Netflix (managing 6 petabytes of data) and Apple (running 160,000+ nodes), Cassandra eliminates single points of failure through a masterless architecture. It utilizes the CQL query language and a partitioned row store to handle massive write throughput while maintaining sub-millisecond latency. The system guarantees regional outage survival via configurable replication factors and tunable consistency levels: making it the industry standard for global, always-on applications.

https://cassandra.apache.org