What is Amazon Relational Database Service (Amazon RDS)?

Amazon Relational Database Service (Amazon RDS) is a web service that makes it easier to set up, operate, and scale a relational database in the AWS Cloud. It provides cost-efficient, resizable capacity for an industry-standard relational database and manages common database administration tasks.

Amazon Elastic Compute Cloud (Amazon EC2) provides scalable computing capacity in the AWS Cloud. Amazon EC2 eliminates your need to invest in hardware up front, so you can develop and deploy applications faster.
When you buy an on-premises server, you get CPU, memory, storage, and IOPS, all bundled together. With Amazon EC2, these are split apart so that you can scale them independently.
For a relational database in an on-premises server, you assume full responsibility for the server, operating system, and software. For a database on an Amazon EC2 instance, AWS manages the layers below the operating system.
In this way, Amazon EC2 eliminates some of the burden of managing an on-premises database server.

Amazon RDS is a managed database service. It's responsible for most management tasks. By eliminating tedious manual tasks, Amazon RDS frees you to focus on your application and your users
Amazon RDS over Amazon EC2 as your default choice for most database deployments.

You can use the database products you are already familiar with: Db2, MariaDB, Microsoft SQL Server, MySQL, Oracle, and PostgreSQL.
Amazon RDS manages backups, software patching, automatic failure detection, and recovery.
You can turn on automated backups, or manually create your own backup snapshots
You can use these backups to restore a database. The Amazon RDS restore process works reliably and efficiently.

A DB instance is an isolated database environment in the AWS Cloud. The basic building block of Amazon RDS is the DB instance.
Your DB instance can contain one or more user-created databases.
You can access your DB instance by using the same tools and applications that you use with a standalone database instance
You can create and modify a DB instance by using the AWS Command Line Interface (AWS CLI), or the AWS Management Console.

A DB engine is the specific relational database software that runs on your DB instance. Amazon RDS currently supports the following engines:

Day 12: AWS | RDS (Relational Database Service)