What allows a default ACL to be applied automatically to files created within a directory?

A default ACL (Access Control List) is applied to files created within a directory through the mechanism of inheritance. When a directory is configured with a default ACL, any new files or subdirectories created within that directory will inherit the ACL permissions specified as the default. This behavior ensures that newly created items follow the permissions set at the directory level, facilitating consistent security management without requiring manual permission adjustments for each new file or directory.

For example, if a directory has a default ACL that grants read and write permissions to a specific user or group, any new files created in that directory will automatically have those permissions assigned, unless overridden by another permission setting.

This inherited characteristic of default ACLs is crucial for effective security and access control in managing file systems, particularly in collaborative environments where multiple users interact with shared directories.