VMMVirtual Machine Manager 2008 R2 had support for Virtual Machine templates (VM templates). At their core, VM templates consist of three main artifacts: one or more virtual disks, a hardware profile (define hardware characteristics of the virtual machine) and a guest OS profile (define Windows Operating System specialization values for the virtual machine). VM templates are great for repeatedly and reliably deploying standalone (read: single) virtual machines, but they suffer from at least three notable limitations. 

For the full article, head on over to http://blogs.technet.com/b/scvmm/archive/2012/07/31/an-in-depth-look-at-virtual-machine-manager-services-part-1.aspx.