Amazon RDS is primarily focused on managing which type of databases?

Amazon RDS (Relational Database Service) is specifically designed to manage relational databases, which are structured to store data in a format that allows for easy access and organization. Relational databases use tables to format data and make use of Structured Query Language (SQL) to perform both data manipulation and data definition operations.

The RDS service supports several popular relational database engines, including MySQL, PostgreSQL, Microsoft SQL Server, Oracle, and MariaDB. This service automates tasks such as hardware provisioning, database setup, patching, and backups, which greatly simplifies the management of databases for users.

In contrast, other types of databases that were listed—such as NoSQL, in-memory, and graph databases—do not fall under the primary focus of Amazon RDS. Instead, Amazon provides other services like DynamoDB for NoSQL, ElastiCache for in-memory data, and Neptune for graph databases. Each of these services is tailored to handle specific data models and access patterns that differ significantly from those of relational databases. Hence, RDS is mainly concerned with serving the needs of applications that utilize structured data and relational models.