What is a Virtual Machine? | Definition & Key Features!

The virtual machine is a perfectly isolated software container that allows it to run its operating system and applications, just like a physical computer.

Virtual Machine (VM) Definition

What is a Virtual PC?

The virtual machine (VM) behaves exactly like a physical computer, including its CPU, RAM, hard drive, and virtual network interface cards. In terms of computers, a VM is software that creates a virtual environment between the computer system that hosts it and the end-user, allowing specific software to run.

The primary logic is to enable multiple operating systems to run on the same hardware. The heart of the system is known as a virtual monitor, which runs on hardware and provides several virtual machines (VMs) for the software level. In this way, each may be running a different operating system and may not interfere with the others.

This virtual pc idea is also used in compiled programming languages. In these cases, the goal is to compile program resources tailored to a specific machine. This machine does not even need to exist physically. Also, the VM can run these programs regardless of the operating system.

Creating these virtual environments requires powerful software. Installing Workstation 17 Pro on your computer from scratch is much simpler than you might think. If you follow the step-by-step guide, you’ll be ready in ten minutes. I’ve been using this tool flawlessly for years in my own tests.

Virtual Machine Characteristics

An operating system cannot distinguish between the virtual machine (VM) and the physical machine, or between applications, or other computers on a network. Even the virtual pc itself sees it as a “real” pc. However, a machine consists of software only and does not contain any hardware components. The result is that machines offer several advantages over physical hardware.

Relevance

It is compatible with standard x86 operating systems, such as Windows and Linux, as well as hardware and application drivers designed for these operating systems. The virtual system has a motherboard, a VGA card, and a network card controller, which contains all the components of a physical server.

Similarly, applications developed for any standard operating system, such as Windows, Linux, NetWare, or Solaris, that are ready for use, can run on the VM. Machines should not have particular requirements to make them suitable for virtualization. In this sense, a virtual pc is the same as a physical machine. That is, customers do not need to make adjustments to run applications. All applications that can run on the client’s physical servers also run on machines.

Virtual Machine Isolation

Although virtual PCs can share the physical resources of a single computer, they remain entirely isolated from each other as if they were independent machines. For example, if there are four machines on a single physical server and one of them fails, the other three remain available. Isolation is a key factor in explaining why the availability and protection of applications running in a virtual environment are superior to those running in a traditional, non-virtualized system.

Encapsulation

A VM is essentially a software container that bundles an operating system and all associated applications into a single software package, along with a complete set of virtual hardware resources. Encapsulation makes the machines extraordinarily portable and easy to manage. For example, you can move and copy a virtual PC from one place to another, just as you would any other software file. Alternatively, you can save a virtual PC on any standard data storage medium, ranging from a USB stick to a company’s domain network.

Hardware Independence

Virtual computers are entirely independent of their underlying physical hardware. For example, you can configure a virtual pc with virtual components (such as CPU, network card, and SCSI controller) that are entirely different from the physical components found in the basic hardware. Machines on the same physical server can run various types of operating systems, including Windows, Linux, and others.

Virtual Machine and Physical Machine Comparison

While a physical server is actually a metallic piece, a virtual PC should be considered a collection of software that has been converted into files; these files are encapsulated, meaning they are collected and organized in containers. Like files, virtual machines can be copied, moved, distributed, or emailed, and virtual machine files can be distributed to any medium large enough to be stored. This includes everything from a memory stick, DVD, or hard drive.

On the contrary, it is much more difficult to move or copy physical machines. For first-time users, applications on a physical machine are usually installed instead of just copied. Thanks to the encapsulation as a file, virtual machines are much more portable than physical machines.

The portability of virtual machines as files significantly improves management convenience and provides a great advantage for customers. Fully configured systems, applications, operating systems, BIOS, and virtual hardware can be seamlessly migrated from one physical server to another in seconds, without interruption to maintenance and with continuous workload consolidation.

The second main difference between virtual and physical machines is that virtual machines are entirely independent of physical hardware. The virtual machine may have a network card, VGA card, or SCSI controller, but these components do not interact with the basic hardware of the physical machine in which they are located. The virtual system can run on a physical server with an X-branded network card, but you will always see a VMware virtual network card. In addition, the VM cannot see brand X’s network card.

The 6 Most Asked Questions About Virtual Machines

How different is a virtual machine from a real computer?

Actually, there is almost no difference because a VM acts like a physical PC. It has its own CPU, RAM, and hard disk, and even a network card.

But there is one huge difference: The virtual machine is made fully of software. The operating system inside it thinks it is real hardware.

For example, I tell my clients this: A VM is a perfect copy of a real computer. Until you copy it as a file and put it on a USB stick.

Why would I want to run more than one operating system on a single computer?

Let us say you use Windows but you need to test a program that runs on Linux. Thanks to virtual machines, you can jump into that setup right away without restarting your computer.

You can even use them at the same time. While you write in Windows, your Linux server keeps running in the background.

In other words, each VM lives in its own world and does not mess with the others. This is truly worth gold for developers.

Can VMs harm each other? They definitely cannot, right?

Even though they share resources on the same physical server, they stay fully isolated. If one of four virtual machines crashes, the other three keep running as if nothing happened.

Because each VM has its own operating system and apps. It is as if there is a glass wall between them.

Thanks to this isolation, even a virus that infects one cannot jump to the others. Honestly, VMs are perfect for security testing.

Is it hard to move a virtual machine to another computer?

The best part is right here, because a VM is actually just a file. Just like you copy a Word document, you can put a virtual machine on a USB stick.

You can even send it by email, as long as the file size is not a problem. Do not even compare it to moving a physical computer.

Switching from one server to another finishes in seconds. Plus, you do not need to shut down or restart, which is a big plus.

Can different brand computers run the same VM?

Yes, and this is truly the miracle of hardware independence. The virtual machine never sees the physical hardware below because it is given virtual parts.

For example, even if your computer has an Intel network card, the VM thinks a VMware virtual network card is plugged in. This way it runs the same everywhere.

Two VMs on the same physical server can be one Windows and one Linux. Hardware difference is never a problem for them.

In which situations do virtual machines save the day?

Think about needing to test an old program, but it only runs on Windows XP. You set up a virtual machine, install XP inside, and when the job is done, you delete the file.

Or you want to take a backup before a big update. You can make a copy of the VM and test safely, and if there is a problem, you go back to the old state.

In the end, it is a must-have tool for developers, system admins, and even students. Once you get used to it, going back to a real computer feels hard.

Conclusion

This means that even if the two physical servers are from two completely different manufacturers, a virtual machine can switch from one physical server to another without making changes to device drivers, operating systems, or applications.

Several virtual machines installed on the same physical server can even run different operating systems.

What you’ve read so far might sound complicated. But you’ll see how enjoyable it is when you put it into practice.

Picture this: You open the program and start the helper tool to create your first virtual machine step by step. You decide everything, from the operating system choice to the amount of RAM. A small but useful detail; the setup helper sorts out all the work for you.

What is a Virtual Machine and What Does It Do?