We dont have any documentation to differentiate Windows System Center Orchestrator and vRealize automation
Microsoft System Center Orchestrator was introduced as part of the Microsoft System Center 2012 suite as a rebranding of Microsoft’s previous workflow automation software, Opalis vNext. Orchestrator uses a drag and drop graphical interface to allow admins to define run books. Orchestrator translates these visual representations into .NET scripts, PowerShell or SSH commands to automate workflows. It is capable of managing multiple operating systems and can also handle VMware- and Citrix-based workflows
Sincerely,
Rahul Parmar
VMware Support Moderator