A resource group is the container to which you add one or more VMs and datastores that you want to protect; called a backup job in Virtual Storage Console (VSC). For example, you can simultaneously back up all the VMs that are associated with a given application, or you can back up a single VM, or you can back up all the VMs in a datastore. Resource groups can contain any combination of VMs and datastores.
To back up a single resource, you must create a resource group that contains that single resource.
To back up multiple resources, you must create a resource group that contains multiple resources.
To optimize Snapshot copies, you should group into one resource group the VMs and datastores that are associated with the same volume.
Although it is possible to create a resource group without a backup policy, you can only perform data protection operations when at least one policy is attached to the resource group. You can use an existing policy or you can create a new policy while creating a resource group.