Cloud Databases are fully managed database services — relational, document, key-value, wide-column, graph, time-series, vector — operated by the provider with the customer responsible for schema, queries, and data rather than infrastructure, patching, or HA topology. Core capabilities include automated provisioning and scaling, multi-AZ and multi-region replication, point-in-time recovery, managed major-version upgrades, observability and query insights, and increasingly serverless and consumption-based pricing. The category spans hyperscaler offerings (Amazon RDS/Aurora, Google Cloud SQL/Spanner, Azure SQL), independent multi-cloud vendors (MongoDB Atlas, CockroachDB), and new-era serverless databases (PlanetScale, Neon, Supabase, Turso) designed around developer ergonomics.