- CloudFormation is the native offering from AWS. Templates are submitted in the form of YAML or JSON documents.
- CDK compiles Typescript and other languages down to CloudFormation Templates
- Terraform uses the AWS API directly via an AWS-specific provider, and does not typically use CloudFormation stacks (though this can be useful, in some circumstances!)
- Pulumi uses TypeScript and other languages to drive an engine similar to Terraform (and the Terraform AWS provider is one of the options for provisioning AWS resources).
- CDK compiles Typescript and other languages down to CloudFormation Templates
- Terraform uses the AWS API directly via an AWS-specific provider, and does not typically use CloudFormation stacks (though this can be useful, in some circumstances!)
- Pulumi uses TypeScript and other languages to drive an engine similar to Terraform (and the Terraform AWS provider is one of the options for provisioning AWS resources).
Hopefully this clears it up?