From VM or from vApp templates stored in a content library, you can deploy virtual machines and vApps on hosts or clusters in your vSphere inventory.
The library can be a local library to the vCenter Server instance where you want to deploy the VM or the vApp template, or can be a subscribed library to that vCenter Server instance.
The use of templates brings about consistency, compliance, and efficiency when deploying virtual machines and vApps in your vCenter Server instance.