A virtual machine lets you run an operating system and application window on your desktop that creates a complete, separate computer. You can use them to play around with different operating systems, run software on your main operating system, and test applications in sandbox environments.
There are many free virtual machine (VM) tools out there, which make setting up a virtual machine something anyone can do. You will need to install the VM tools and get the installation media for the operating system you want to install.
What is a Virtual Machine?
A virtual machine creates an environment, called a virtual machine, that simulates a separate computer system, complete with virtual hardware devices. The virtual machine runs as a process in a window in your current system. You can boot an OS installation disk (or live CD) into a virtual machine, and the OS will be pretended to be running on a real computer. It will install and run just like it would on a real machine. Whenever you want to use the operating system, you can open the virtual machine program and use it in your current window and desktop.
In the world of virtual machines, the operating system running on your computer is called the host, and all the operating systems running in the virtual machine are called guests. This helps make things less complicated. In a fully virtualized machine, the guest operating system is stored on a virtual hard disk, a large file of several gigabytes stored on your real hard disk. The VM appliance presents this file to the guest operating system as a real hard drive. This means you don’t have to worry about partitioning or doing anything else to mess with your real hard drive.
Virtualization adds overhead, so don’t expect it to be as fast as if you installed the OS on real hardware. Looking for games or other applications that require intensive graphics and CPU power is not very efficient, so a virtual machine is not the best way to play PC games on Windows and Linux or Mac OS X – at least, unless those games very grown up. or not graphically demanding.
The limit on the number of virtual machines you can have is only limited by hard drive space. Here’s a look at some of the virtual machines we use to test things while writing articles. As you can see, we have a full VM with several versions of Windows and Ubuntu installed. You can also run multiple virtual machines at the same time, but you will find yourself using less of your system resources. Each virtual machine consumes CPU time, RAM and other resources.
Why should you create a virtual machine?
Besides being fun for geeks, virtual machines provide many important uses. They allow you to try out another operating system without installing it on your physical hardware. For example, they are a good way to play with Linux – or a new Linux distro – and see if it works for you. After you finish using the OS, you can delete the VM. Virtual machines also allow you to run software from other operating systems. For example, as a Linux or Mac user, you can install Windows on a virtual machine to run Windows applications that you may not otherwise have access to. If you want to run another version of Windows, such as Windows 10, but have older applications that only run on XP, you can install Windows XP in a virtual machine.
Virtual Machines APPS
You can choose from several virtual machine programs:
- VirtualBox: (Windows, Linux, Mac OS X): VirtualBox is very popular because it is open-source and completely free. There is no paid version of VirtualBox, so you don’t have to deal with the usual annoyances and “upgrades to get more features”. VirtualBox works well, especially on Windows and Linux where there is little competition, which makes it a good start in virtual machines.
- VMware Player: (Windows, Linux): VMware has a line of virtual machine programs. You can use VMware Player on Windows or Linux as a free virtual machine tool. More advanced features, many of which are free in VirtualBox, require an upgrade to the paid VMware Workstation program. We recommend starting with VirtualBox, but if that doesn’t work well, you can try VMware Player.
- VMware Fusion: (Mac OS X): Mac users must purchase VMware Fusion to use VMware products, as the free VMware Player is not available on Mac. However, VMware Fusion is more refined.
- Parallels Desktop: (Mac OS X): Macs also have Parallels Desktop. Both Parallels Desktop and VMware Fusion for Mac are more polished than virtual machine programs on other platforms, as they are marketed to Mac users who may want to run Windows software.
While VirtualBox works great on Windows and Linux, Mac users may want to purchase a more polished and integrated Desktop or VMware Fusion program. Windows and Linux applications such as VirtualBox and VMware Player tend to appeal to a more geeky audience. There are of course many other VM options. Linux includes KVM, a virtualized solution. Professional and enterprise versions of Windows 8 and 10, but not Windows 7, include Microsoft Hyper-V, a built-in virtual machine solution. These solutions may work well, but they don’t have the most user-friendly interface. RELATED: How to Install KVM and Create a Virtual Machine in Ubuntu
Configure the virtual machine
Once you have selected the VM application and installed it, setting up the VM is really easy. We’ll go through the basic steps in VirtualBox, but many applications manage to create virtual machines the same way. Open your VM app and click the button to create a new virtual machine.
You will be guided through this process by an expert who will first ask you what type of system to install. If you type the name of the operating system in the “Name” box, the application will most likely select the type and version of the operating system. If not, or if it’s a mistake, select these items yourself from the drop-down menu. When you’re done, click “Next.”
Depending on the operating system you plan to install, the wizard will select some default settings for you, but you can change them on the next screen. You will be asked how much memory to allocate to the VM. If you want something other than the default, select it here. Otherwise, just click “Next”. But don’t worry, you can change this value later if necessary.
The wizard will also create a virtual hard disk file that the VM will use. Unless you already have a virtual hard disk file that you want to use, just select the option to create a new one. You will also be asked if you want to create an assigned or fixed hard disk.
With a hard-allocated disk, you can keep the maximum disk size, but the file will only grow to that size as needed. With a limited disk, you will keep the size, but the file created will be as large as the software that created it.
We recommend creating parallel disks because although they consume less disk space, they also perform better, making your virtual machine more efficient. Plus, you’ll know how much disk space you’ve used and won’t be surprised when your VM files start to grow.
You can set the size of the virtual disk. You are free to use the default settings or change the size according to your needs. Once you click “Create”, a virtual hard disk is created. After that, you will be returned to the main VM application window, where your new VM should appear.
Make sure the installation media you want is available on the machine. This usually involves pointing to an ISO file or a real disk from the virtual machine’s settings. You can run your new machine by selecting it and clicking “Start”.
Of course, we covered the basics of using virtual machines here. If you want to know more, check out some of our other guides:
