I keep hearing about "clusters." What is the actual benefit of a database cluster over a standalone node?

A database cluster is a group of interconnected servers that work together to ensure High Availability (HA) and Fault Tolerance. If one node fails, the system automatically reroutes traffic to another node to prevent downtime. Clusters also allow for load balancing, distributing queries across multiple nodes to optimize performance and handle larger transaction volumes. We support clustering for MongoDB, Redis, MariaDB, MySQL, and PostgreSQL