Amazon RDS vs Amazon S3: What are the differences?

What is Amazon RDS? Set up, operate, and scale a relational database in the cloud. Amazon RDS gives you access to the capabilities of a familiar MySQL, Oracle or Microsoft SQL Server database engine. This means that the code, applications, and tools you already use today with your existing databases can be used with Amazon RDS. Amazon RDS automatically patches the database software and backs up your database, storing the backups for a user-defined retention period and enabling point-in-time recovery. You benefit from the flexibility of being able to scale the compute resources or storage capacity associated with your Database Instance (DB Instance) via a single API call.

What is Amazon S3? Store and retrieve any amount of data, at any time, from anywhere on the web. Amazon Simple Storage Service provides a fully redundant data storage infrastructure for storing and retrieving any amount of data, at any time, from anywhere on the web.

Amazon RDS belongs to "SQL Database as a Service" category of the tech stack, while Amazon S3 can be primarily classified under "Cloud Storage".

Some of the features offered by Amazon RDS are:

• Pre-configured Parameters
• Monitoring and Metrics
• Automatic Software Patching

On the other hand, Amazon S3 provides the following key features:

• Write, read, and delete objects containing from 1 byte to 5 terabytes of data each. The number of objects you can store is unlimited.
• Each object is stored in a bucket and retrieved via a unique, developer-assigned key.
• A bucket can be stored in one of several Regions. You can choose a Region to optimize for latency, minimize costs, or address regulatory requirements. Amazon S3 is currently available in the US Standard, US West (Oregon), US West (Northern California), EU (Ireland), Asia Pacific (Singapore), Asia Pacific (Tokyo), Asia Pacific (Sydney), South America (Sao Paulo), and GovCloud (US) Regions. The US Standard Region automatically routes requests to facilities in Northern Virginia or the Pacific Northwest using network maps.

"Reliable failovers", "Automated backups" and "Backed by amazon" are the key factors why developers consider Amazon RDS; whereas "Reliable", "Scalable" and "Cheap" are the primary reasons why Amazon S3 is favored.

According to the StackShare community, Amazon S3 has a broader approval, being mentioned in 3235 company stacks & 1616 developers stacks; compared to Amazon RDS, which is listed in 1437 company stacks and 526 developer stacks.