How do CloudFormation nested stacks and cross stack references help organize very large and complex infrastructure definitions?

Nested stacks let you break a large, complex infrastructure definition into smaller, more manageable and reusable individual templates, such as a separate template for networking and another for the application layer, which are then referenced together as one parent stack, while cross stack references let entirely separate, independently managed stacks share specific output values with each other, both approaches helping organize infrastructure code more cleanly as it grows beyond what is practical to manage within a single, massive template file.

Resources:
  NetworkStack:
    Type: AWS::CloudFormation::Stack
    Properties:
      TemplateURL: https://s3.amazonaws.com/my-templates/network.yaml