Amazon Vpc lets you create a logically isolated section of the AWS cloud where you can launch AWS services in the Virtual Network which you defined. Every region will have its own VPC and later you can connect VPCs of different regions.
Subnets are containers within VPC that segment the CIDR block you have defined your VPC. Subnets allow you to give access rules and place resources in containers where the rules are applied.
For more information about VPC, you can check out aws vpc tutorial by Intellipaat.
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