Virtualization, what is
Although the virtualization concept started in the ’60s, the first public release software was in 2001. But what is actually virtualization. Imagine you need to host a webserver for an app that doesn’t require more than 4Gb of ram, a dual core CPU and 100Gb of storage. Your server is more powerful than that, what will happen with all those extra resources? Nothing, it will just sit idle in the system, not used. This is where virtualization comes in place. By creating a virtual machine with only your needed resources, you leave space for other virtual machines on the same physical server.
By Wikipedia definition “a virtual machine (VM) is the virtualization/emulation of a computer system“.
Now we know it is possible to split our physical machine into several virtual machine. How can we do that? It’s simple, with a hypervisor software. There are two types of hypervisor called Type-1 and Type-2.
Type-1 hypervisor is installed directly on “bare metal” while Type-2 runs on an operating system like Windows, Linux or MacOS. As a VM operating system you can install from Windows 3.1 to the latest version of Windows, every version on Linux or even MacOS.
You can find some hypervisor examples in this list, most of them are free to use even in a commercial environment.
With this type of software, testing, learning and administration is much easier. Have fun with it.