Using virtualisation allows you to create multiple virtual servers running alongside each other on the same physical platform. This allows you to allocate resources, manage workloads better, and keep key services separate.  For example the digital imaging server can be on a different server to your Exact server, both separate from a third server acting as the domain controller and file server. All running on the same physical machine. Even running just one virtual server is better than using only a physical machine, as this makes migrations, backups, restores and upgrades to that server easier, safer and faster.