Transform reference
This section contains reference information for the transforms AWS CloudFormation supports. Transforms are macros hosted by CloudFormation. Unlike custom macros, a transform doesn't require any special permissions to use it because it is hosted by CloudFormation. Transforms can be used in templates in any account within CloudFormation. Also, there is no charge incurred when using transforms. CloudFormation treats a transform the same as any other macro in terms of evaluation order and scope.
For information about using transforms in your templates, see Transform template section. For information about macros, see Using macros to perform custom processing on templates.