Subnets

A subnet is a section of a VPC in which you can group resources based on security or operational needs. Subnets can be public or private.

• Public subnets contain resources that need to be accessible by the public, such as an online store’s website.

• Private subnets contain resources that should be accessible only through your private network, such as a database that contains customers’ personal information and order histories.

In a VPC, subnets can communicate with each other. For example, you might have an application that involves Amazon EC2 instances in a public subnet communicating with databases that are located in a private subnet.