Hi Joe.
Hyper-V in Windows 8 is a native application used to create and manage various Virtual Machines very similar to what you may have seen in other Virtualization Software products like VMware Workstation, VMware Player, Virtual Box and Microsoft Virtual PC.
It has its' own Virtual Machine Manager for constructing the VMs configuring the various settings, CPUs, Memory allotment, Networking, etc., See attached thumbnail.
You can also use the Hyper-V Manager to connect to the VMs and run them like you would normally do but that particular interface has some restriction as to how well it accepts peripherals attached to the host. So typically after I configure a Virtual Machine, install the associated OS and run the integration services setup, I'll configure the machine with a static IP address and then just start the machine with Hyper-V Manager and then use Remote Desktop (mstsc.exe) to actually run the machine.
That way I can configure through the RDP options which devices, like printers, hard drives, USB thumb drives, etc., I want to be available to the Virtual Machine from those attached to the Host Machine.
The single caveat is that the MoBo / Processor has to support Virtualization Technology, which most recent boards do so it's usually not an issue.
Regards
Randy
EDIT: Some additional system requirement enumerated.
http://winsupersite.com/article/windows8/windows-8-feature-focus-client-hyperv-142889