Apache Cassandra is a popular database for several reasons. The open source, distributed, NoSQL database has no single point of failure, so it’s well suited for high-availability applications. It supports multi-datacenter replication, allowing organizations to achieve greater resiliency by, for example, storing data across multiple Amazon Web Services availability zones. It also offers massive and linear scalability, so any number of nodes can easily be added to any Cassandra cluster in any datacenter. For these reasons, companies such as Netflix, eBay, Expedia, and several others have been using Cassandra for key parts of their businesses for many years.