Containers and Virtual Machines: A Guide to Understanding the Difference

Containers and virtual machines both have their place in the modern computing world. While virtual machines are great for testing new operating systems or software applications, they’re not very useful in the age of microservices and cloud computing. Virtual machines work best when you need to run one operating system at a time on dedicated hardware. They’re not very good for isolating processes from each other or separating storage from memory. That’s where containers come in handy. A container is a virtualized version of a process on your computer. It has its own OS kernel, process ID, user account, and accessible files – but it’s all hidden away from the rest of your computer with no direct access to other programs or hardware components. This makes isolating and managing processes much easier than using virtual machines alone.

What is a Virtual Machine?

A virtual machine is a software system that emulates a physical computer. Virtual machines allow users to simultaneously run multiple operating systems on a single computer. Each guest OS runs as if it were installed on a stand-alone computer with its own hardware. A virtual machine is essentially a computer within a computer. It has its own operating system, processor, RAM, and hard drive. The host computer allocates these virtual machines with the same amount of RAM and storage space as it’s given to its own operating system. This means multiple virtual machines can use more resources than the host computer alone.

What is a Container?

A container is a lightweight virtualization technology that allows you to package software into one standardized unit, including the operating system and any dependencies. Once created, a container can be run on any computer with a compatible operating system as if it were a native application. This standardized unit can either be run in a single container or be broken down into smaller micro-containers. The smaller the container, the less overhead is required to run the containers. Containers are far more efficient than virtual machines because they use a fraction of the resources. You can run multiple containers on a single computer or virtual machine while keeping everything isolated from the host system.

Containers vs. Virtual Machines (How Virtualization Works)

Virtual machines and containers both virtualize hardware, but containers have much less overhead. Since containers don’t need to emulate a full computer, they don’t need as much memory or processing power. Containers also don’t need any additional software installed on the host computer since they run off the operating system already installed. Virtual machines, on the other hand, require a hypervisor. The hypervisor software allows the virtual machine to run on the host computer. Virtual machines are more powerful and flexible but require many more resources. Containers are much more resource-efficient but less flexible.

When to Use Virtual Machines

Virtual machines are great for testing new applications or troubleshooting problems. You can install any operating system you like, run multiple OSs simultaneously, or even have one OS host other OSs. Virtual machines are also a good option if you don’t have a lot of hardware to work with. You can install an OS on a virtual machine with less hardware than you’d need to host it directly. Virtual machines are not very good for running microservices. They don’t allow you to scale out or share services between multiple applications. Virtual machines are also not recommended for continuous integration or deployment. A container can be started and stopped much faster than a virtual machine. If a service is down, you can quickly restart the container to avoid a service outage.

When to Use Containers

Containers are great for running microservices in a clustered environment. They allow each service to run as if it were a single process on the host computer. Each service can be broken down into the smallest possible container. This allows for easier maintenance and scaling out of the services. It also makes the services much easier to run in production since they’re self-contained units. Any service can be replicated across a cluster of computers to increase availability. The services can also be run in any language or framework as long as they’re supported by the host OS. When using containers, security is also much easier to implement. Since each service is isolated from the host system, you can apply strict permissions on who can access each container.

Wrapping Up

Virtual machines and containers are both useful for different purposes. Virtual machines are great for testing new applications and troubleshooting. Containers are best for running microservices in a clustered environment. When choosing between virtual machines and containers, consider what your needs are. Virtual machines are the better option if you want to test out new applications. Use containers to scale out and run your applications more efficiently for microservices or cloud-native applications.