RDS Cluster in AWS is a high-availability, multi-node relational database service. Built on the Amazon Aurora engine, it provides enhanced scalability, fault tolerance and durability compared to single node databases. RDS Clusters allow users to create multiple instances with different configurations and workloads in order to achieve maximum performance from their database systems. Each instance can be configured independently for performance or scalability, making it an ideal solution for applications requiring high availability and fast response times. Additionally, RDS Clusters offer automated failover capabilities that allow databases to switch over automatically if one instance experiences an issue or failure.