What you need before you start

A virtual machine runs on your computer like any other program — it takes up disk space and RAM the same way your web browser does. Before you install, check that your computer has enough room and power. You need at least 20 to 30 gigabytes of free disk space for the virtual machine software itself, plus extra space for the operating system you plan to run inside it. If you want to run Windows inside your virtual machine, budget another 20 to 40 gigabytes depending on which version.

Your processor matters more than most people realize. Modern processors from Intel and AMD have built-in features that make virtual machines run faster — Intel calls theirs VT-x, and AMD calls theirs AMD-V. If your computer is more than five years old, check your processor's specifications on the manufacturer's website. Older machines can still run virtual machines, but they will be noticeably slower.

RAM is the third piece. Virtual machine software itself uses 2 to 4 gigabytes, and the operating system running inside uses another 2 to 8 gigabytes depending on what you plan to do. If your computer has 8 gigabytes total, you can run a basic virtual machine, but you will feel the slowdown when you switch between your main system and the virtual one. 16 gigabytes or more gives you room to work comfortably.

Key Takeaways

  • Virtual machine software like VirtualBox (free) or VMware Workstation Player (free for personal use) installs on your existing operating system the same way any other program does.
  • After installation, you create a new virtual machine by allocating disk space and RAM, then install an operating system inside it from an ISO file or installation media.
  • Your processor must support virtualization features — check your BIOS settings to turn on VT-x (Intel) or AMD-V (AMD) if it is not already enabled.
  • The whole process from read to running a second operating system takes 30 minutes to two hours depending on your internet speed and which operating system you choose.

Choosing between VirtualBox and VMware Workstation Player

The two most common choices for home and small business use are VirtualBox and VMware Workstation Player. Both are free for personal use, and both work on Windows, Mac, and Linux. VirtualBox is open-source, meaning the code is public and volunteers maintain it. VMware Workstation Player is made by a company and has more polished features, but fewer people use it for learning.

For your first virtual machine, VirtualBox is the simpler choice. It has fewer settings to configure, the interface is straightforward, and if something goes wrong, more tutorials exist online because more people use it. read it from virtualbox.org — make sure you get the version for your operating system (Windows, Mac, or Linux). The file is about 100 megabytes and takes a few minutes to read on a typical home internet connection.

If you want to try VMware instead, go to vmware.com and read Workstation Player. The installation process is nearly identical to VirtualBox, and the steps that follow work the same way. The choice between them matters less than getting started — you can always switch later.

Installing VirtualBox on your computer

Once the VirtualBox installer downloads, open it like you would any other program installer. On Windows, double-click the .exe file. On Mac, open the .dmg file and drag VirtualBox into your Applications folder. On Linux, use your package manager or run the installer from the command line — the exact command depends on your distribution, so check the VirtualBox read page for your specific version.

The Windows installer will ask you a series of questions. Accept the default location unless you have a reason to change it. When it asks about network adapters, leave those checked — VirtualBox needs them to let your virtual machine connect to the internet. The installation takes two to five minutes. When it finishes, restart your computer.

After restart, open VirtualBox from your Applications menu (Mac), Start menu (Windows), or process launcher (Linux). You should see an empty window with a blue VirtualBox logo and a menu bar at the top. If you see this, the installation worked. If you get an error message about missing files or permissions, restart your computer again — sometimes the system needs a second restart to finish setting up the background services VirtualBox uses.

Enabling virtualization in your BIOS

Before you create your first virtual machine, check that your processor's virtualization feature is turned on. This setting lives in your BIOS — the firmware that runs before your operating system starts. On most computers made after 2010, this feature is on by default, but some manufacturers turn it off.

To check, restart your computer and watch the screen as it boots. You will see a message that says "Press Delete to enter Setup" or "Press F2 to enter BIOS" or something similar — the key varies by manufacturer. Press that key before Windows or Mac loads. You will see a text-based menu that looks nothing like your normal operating system. Look for a section called "Processor", "CPU", "Virtualization", or "Security". Inside that section, find a setting called "VT-x" (Intel), "AMD-V" (AMD), or "SVM". If it says "Disabled", change it to "Enabled". Save your changes and exit — usually by pressing F10 or selecting "Save and Exit".

If you cannot find this setting, or if your computer will not let you change it, your processor may not support virtualization, or your computer's administrator has locked the BIOS. Check your processor's specifications on Intel.com or AMD.com by searching for your processor model number. If virtualization is not supported, virtual machines will still work, but they will run much more slowly.

Creating your first virtual machine

Open VirtualBox and click the blue "New" button in the toolbar. A window will appear asking for a name and operating system. Type a name like "Windows 11 Test" or "Ubuntu Practice" — this is just for you to keep track of which machine is which. Then select the operating system you want to run inside the virtual machine. If you want to run Windows, select "Windows" and then the specific version. If you want to run Linux, select "Linux" and then the distribution like "Ubuntu".

The next screen asks how much RAM to give your virtual machine. The slider shows a recommended amount in green. For Windows, that is usually 4 gigabytes. For Linux, 2 gigabytes is often enough. Do not go below the green recommendation unless your computer has very little RAM. Click "Next".

The next screen asks about disk space. Select "Create a virtual hard disk now" and click "Next". Choose "VDI" as the disk type — this is VirtualBox's native format and works best. On the next screen, choose "Dynamically allocated" — this means the virtual disk starts small and grows as you add files, rather than taking up all the space when ready. Set the size to 40 gigabytes for Windows or 20 gigabytes for Linux. This is the maximum the virtual disk can grow to, not the amount it uses right now.

Click "Create" and wait. VirtualBox will create the virtual hard disk, which takes a minute or two. When it finishes, you will see your new virtual machine listed on the left side of the VirtualBox window. It is not running yet — you have only created the container.

Installing an operating system inside the virtual machine

To actually use your virtual machine, you need to install an operating system inside it. You will need an ISO file — a single file that contains everything needed to install the operating system. For Windows, you can read an ISO from Microsoft's website. For Linux, go to the distribution's website — Ubuntu.com for Ubuntu, Fedora.org for Fedora, and so on. The ISO file is usually 3 to 6 gigabytes, so read it while you have time.

Once the ISO downloads, select your virtual machine in VirtualBox and click "Start". A window will open, and VirtualBox will ask you to select an installation medium. Click the folder icon and navigate to the ISO file you downloaded. Select it and click "Open". VirtualBox will start the virtual machine and boot from the ISO, just like you were installing the operating system on a real computer.

From here, follow the normal installation steps for that operating system. For Windows, you will see the Windows Setup wizard — choose your language, accept the license, and select the virtual hard disk you created earlier as the installation destination. For Linux, you will see the distribution's installer — choose your language, timezone, and disk, then let it install. The installation takes 10 to 30 minutes depending on your internet speed and how fast your computer is.

When the installation finishes, the virtual machine will restart and boot into the new operating system. You now have a fully working second operating system running inside your main computer. You can use it exactly like a real computer — install programs, browse the internet, create files. When you are done, close the window or click the power button inside the virtual machine to shut it down.

Making your virtual machine faster and easier to use

After you install the operating system, install VirtualBox Guest Additions — a set of tools that make the virtual machine run faster and behave more like a normal window. Inside the virtual machine, click "Devices" in the menu bar and select "Insert Guest Additions CD Image". The virtual machine will mount a CD, and you will see an installer. Run it and restart the virtual machine when it finishes.

Guest Additions does three important things: it makes the mouse move smoothly between your main computer and the virtual machine without getting stuck, it lets you resize the virtual machine window and have the screen resize automatically, and it speeds up graphics so the virtual machine does not feel sluggish. Without it, moving the mouse feels jerky and resizing the window is awkward.

You can also take a snapshot before you make big changes. In VirtualBox, right-click your virtual machine and select "Snapshots". Click "Take Snapshot" and give it a name like "Clean Install" or "Before Software Update". If something goes wrong later, you can restore to that snapshot and undo the changes. This is one of the biggest advantages of virtual machines — you can experiment without risk.

Frequently Asked Questions

Can I run my virtual machine and my main operating system at the same time?

Yes. The virtual machine runs as a window on your main computer, so you can switch between them like you would switch between your web browser and email. Your main operating system keeps running in the background. If you close the virtual machine window, the virtual machine shuts down, but your main system continues working normally.

What if I run out of disk space on my virtual hard disk?

You can expand the virtual hard disk after creation. In VirtualBox, go to File, then Disk Management, then Virtual Media Manager. Select your virtual disk and click the expand button. You can increase the size, but you also need to expand the partition inside the operating system — this requires tools like GParted for Linux or Disk Management for Windows. It is easier to allocate enough space when you create the machine.

Can I move a virtual machine to a different computer?

Yes. Virtual machines are just files on your disk. You can copy the entire virtual machine folder to an external drive or another computer, and as long as that computer has VirtualBox installed, you can open and run it. This is one reason virtual machines are useful for testing — you can move them around easily.

Why is my virtual machine running slowly?

The most common reason is that you did not allocate enough RAM. If your main computer is using most of its RAM, the virtual machine will be slow because it has to share. Close other programs on your main computer, or increase the RAM you gave the virtual machine in its settings. The second reason is that you did not install Guest Additions — do that first and restart.

Do I need to pay for virtual machine software?

No. VirtualBox and VMware Workstation Player are both free for personal use. You only pay if you want advanced features like snapshots with branching (multiple versions of the same machine) or if you use them for a business. For learning and testing, free software is enough.