Virtualization and Cloud Computing Are Not the Same Thing
If you aren’t sure what the difference is, don’t feel too bad. Most people don’t understand the subtle distinction, and many actually conflate the two concepts as one in the same. Even tech-savvy folks, like the ones you’d ask to fix your computer , get them mixed up all the time.
And it doesn’t help that “the cloud” has become an overused buzzword that describes everything from cloud computing to cloud storage and beyond.
So what’s the difference? And why should you care, anyway? As it turns out, both of these things can come in handy for you once you know what they are and how they provide value — so much so that if you aren’t taking advantage already, you’re missing out on a lot.
Virtualization is when you create a virtual representation of something physical. Virtual reality, for example, is just a representation of physical reality with some tweaks and differences. But in the context of computers, virtualization is slightly more specific.
Virtualization is when you take physical resources (such as RAM, CPU, disk space, etc.) and split them up into discrete chunks that are seen as separate by the system. Each chunk can be dedicated to different users, and because the chunks are discrete, users can only use the resources that are assigned to them.
Virtual Machine Example
A “virtual machine” is a program that creates a virtual computer on your system, and this virtual computer can run its own operating system that’s separate from your actual operating system. The actual system is called “host” while the virtual system is called “guest”.
Let’s say you’re running Windows. That’s your host OS. Using virtual machine software like VirtualBox, you can install and run a copy of Ubuntu from within Windows. It runs in a window like any other program, except it’s limited to however much RAM, CPU, disk space, etc. that you set aside when the virtual machine is created.
Virtual machines are the best way to run multiple OSes on one machine , assuming you have enough physical resources to divvy up. The nifty thing is that because the resources are set aside as their own little sandbox, you can catch a virus in the guest OS and it won’t affect your host OS. As such, virtual machines are the recommended way to test new OSes and programs .
Virtual Server Example
As a casual home user, you’d probably never run more than one virtual machine at a time, so at most you’d have one host OS and one guest OS. But on the business side, it’s not uncommon to find computers that run several virtual machines alongside one another, resulting in one host OS and dozens or even hundreds of guest OSes.
When this happens, the computer is often referred to as a “virtual server”. This obviously requires an extremely powerful system with top-of-the-line specifications, otherwise there wouldn’t be enough resources to split and each virtual machine would slow to a crawl. Powerful computers are expensive, so that’s why virtual servers are usually only run by businesses.
But why would a business want to do this? That’s a good question, and that leads us to the concept of cloud computing.
What is “the cloud” ? Well, you can think of it as a remote cluster of servers that provides a service — or in layman’s terms, a bunch of interconnected computers (cluster of servers) that are accessible from anywhere as long as you have internet connectivity (remote) that provide a service, whether free or paid.
Cloud computing is when you use computers on the cloud to process or store data, thus freeing up your own computer’s resources (i.e. processing power and storage space). Note that some cloud services make use of virtualization, but many don’t.
Simple Service Example
If you use Gmail, then you’re already using a cloud-powered service. In this case, all of your email data is stored on Google’s network of servers and Google’s servers do all of the heavy lifting in terms of sending, receiving, and processing that data — the computing is done on the cloud, not your own computer.
The same is true for most web-based services, such as calendars, to-do lists, social networks, VoIP, remote data storage, budget managers, online photo editors, etc.
Advanced Service Example
Some cloud services are more advanced than others. For example, email hosting on Gmail or Outlook.com is relatively simple when compared to collaborative document editing on Office Online, Google Docs, or any of the other online office alternatives.
On Google Docs, every document or spreadsheet is hosted on Google’s servers. When you open a file and start editing it, you’re actually interacting with a file that’s thousands of miles away, which is why someone else can open the same file and edit it at the same time. Google’s servers are processing your inputs in real-time.
Virtual Hosting Example
Notice how the above examples had no mention of virtualization? Here’s one that does.
When you sign up for a shared web hosting plan , it’s usually hosted on a single machine without any virtualization, and dozens of others are using that same server. If one user makes a mistake and locks up the server’s CPU, everyone’s website goes down until the server is fixed.
But when you sign up for a virtual private server plan, you’re still on a single machine but your portion of the server’s resources is virtualized. If one user makes a mistake, they only lock up their portion of the server’s CPU and only their website goes down. Yours remains untouched. This is why VPS hosting is preferable to shared hosting .
And then you have services like Amazon Web Services, which uses a cluster of virtualized servers to provide cloud computing to multiple users. The benefit here is that your account doesn’t reside on any single computer — it resides on the entire cloud, so if one physical server happens to die, your website won’t die with it.
The Future of Tech Is the Cloud
You can have virtualization without the cloud, and you can have cloud computing without virtualization. The two are usually combined but they don’t have to be. Hopefully you now know the difference between the two!
By this point, most people are surprised by how much cloud computing they actually use on a day-to-day basis. Maybe you’re feeling the same. I personally love the convenience of the cloud, but you should beware that there are some risks to cloud computing to avoid .
And if you find it particularly interesting, consider a career in cloud computing !
Did this clear up any confusions you may have had? Got any questions still lingering in your mind? Feel free to share with us in the comments below.
Image Credit: everything possible via Shutterstock.com