You use the Orchestrator client to run and create workflows and access the plug-in API. You can use either the embedded vRealize Orchestrator instance in your vRealize Automation installation, or an external vRealize Orchestrator server.
vRealize Orchestrator powers the vRealize Automation plug-in. vRealize Orchestrator is a development and process-automation platform that provides a library of extensible workflows to manage the VMware cloud stack and third party technologies.
vRealize Orchestrator allows integration with management and administration solutions through its open plug-in architecture.