Data Owner or Data Controller: individual in the org who is responsible for protecting the data and holds the legal rights, defines policies
Data Processor: the entity responsible for processing the data, typically the cloud provider
Data Custodian: technical responsibility over the data , security, continuity, backups, restoring, etc, implementing business rules
Data Steward: governance quality and compliance of data, ensuring the data is in the right form
Data Subject: the individual to whom the data relates