A VMware template includes the virtual machine's virtual disks and settings from its .vmx configuration file, managed with permissions. Templates save time and avoid errors when configuring settings and other choices to create new Windows or Linux server VMs. They can also be used as long-term in-place backups of VMs, and to ensure consistent VMs are created and deployed across a company. A VMware template cannot be operated without reverting it to a virtual machine (VM).
Here is original Vmware 5 article on this argument but you can easily find tons of articles on this argument:
https://pubs.vmware.com/vsphere-50/index.jsp#com.vmware.vsphere.vm_admin.doc_50/GUID-9062F225-E01B-42BA-8AFB-8EA4069068FE.html
Here is Vmware .pdf White Paper:
http://www.vmware.com/pdf/vc_2_templates_usage_best_practices_wp.pdf
