Amazon RDS (Relational Database Service) is a managed database service provided by AWS. It makes it easy to create, operate, and scale relational databases in the cloud without managing the underlying servers.
With Amazon RDS, AWS handles tasks such as database setup, backups, software patching, monitoring, and scaling. It supports database engines like MySQL, PostgreSQL, MariaDB, Oracle, and Microsoft SQL Server.
In simple words, Amazon RDS lets you run relational databases in AWS while AWS manages the maintenance, so you can focus on your applications.