So you only have one computer (Lets assume running Windows) that you’d like to do virtualization stuff as well without screwing with Windows or your files. Lucky you, I actually made a video on doing this with an application called Virtual Box. Within the video I go over rather quickly how to spawn an instance of Ubuntu and how to map a usb device to said virtual machine. This can be useful if you’re having issues with your local machine and other hardware or is great as a test environment that could keep harmful activities off of your host machine.
So you have one beefy super computer or even dedicated server hardware, what do you do with it? Why not multitask! Personally, I use software known as Proxmox. What this software allows one to do is basically spawn multiple machines within one machine. So for instance, with one physical computer, you could in theory create multiple virtual computers under the same machine. This is useful if you need to run independent services or even create inner network redundancy. Proxmox does so much that I can’t even begin to go over everything so you’ll just have to experiment! Proxmox is entirely free to use and open source which is why I embrace their software. Proxmox has a very straight forward self-guided installer that even beginners can use to get started. Just download their latest version and burn it to a CD. Then use your new hardware to boot the CD like an installation disc and it’s off to the races.