What is Docker and How Does it Work?

Docker separates applications from the operating system by using container technology, much in the same way that virtualization separates a virtual machine from bare metal. Resources are provisioned and fed to these compartmentalized instances so that they always have what they need. 

When you deploy your application to a virtual machine, you have a lot of overheads to worry about thanks to the operating system that the application runs on. This can create performance issues for applications that haven’t been properly tested in every single environment, which is another variability that creates instability with application deployments.

Docker avoids this completely by virtualizing the operating system and running the application in an environment that is exactly as it was in the development environment. This takes out the guesswork and avoids surprises when it comes time to deploy to a live environment.

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4 Key Benefits of Using Docker

Now that we have had a chance to find out about containerization, what are some benefits that Docker can offer?

Scalability: Scaling up and scaling down is very easy thanks to the lightweight nature of docker containers. This means that when you need more containers, you can just fire them up. When you don’t need them anymore, just simply shut them down.

Density: Isolated containers use far fewer resources than traditional application servers, even virtualized ones. This means that fewer machines are needed, reducing licensing costs and improving the overall performance of your applications. 

Portability: Dockerized applications can be moved around very easily. You can simply take a snapshot of a container, upload it to a registry, and then start making containers from it.   

Deployability: Deploying a docker container is much easier than provisioning a physical or virtual application server. Docker can be deployed to just about any computer, including desktops, laptops, servers, and virtual machines.

There are many other benefits to using Docker, but the main takeaway is that Docker is built to speed up the software development lifecycle. (SDLC) 

The whole process of deploying and refactoring your applications is greatly sped up, meaning that your applications will be refined and updated much faster, easier, and more efficiently.

Why You Should Use Docker

There are so many reasons why you should be thinking about using Docker. The first and most obvious reason is that you can build any application that you want, in any language that you prefer, using the technology stack of your choice.

This is huge!

Dockerized apps are renowned for being able to run on just about anything, from laptops to virtual machines - which means that they don’t need much in the way of system resources in order to be deployed. 

Thanks to the containerized structure of these apps, there are no software dependency nightmares, application version mismatches, or patch-level requirements to satisfy in order to run your container. Everything is nested within the Docker container, which means that no matter where you fire it up, it will be running in the environment that it needs to work properly.

See also: How Kerberos Works in Windows Active Directory.

Final Thoughts

Now that we have gone into some of the basics of what Docker is, what it does, and why you should use it, let’s summarize some of the main points.

• Companies like Google rely on container technology to run their business. Docker makes it easy to use containers, and Microsoft now supports it in Windows too.

• Docker separates applications from the underlying operating system that it runs on, just like virtual machines do. This makes it extremely fast, and extremely portable, and we don't have to worry about the operating system.

• Docker containers are lightweight and can be scaled up and down very fast. They can be moved around very easily and can be deployed almost anywhere.

• Docker dramatically reduces the entire development lifecycle from development to testing to deployment.

All of these reasons explain why Docker has become such a popular platform for DevOps. It allows you to get your products out faster, and deployed easily and at scale. 

Docker has paved the way for many other technologies that benefit from running in small containerized environments.

Docker is here to stay, and containerization is essential for modern organizations that need to operate globally and deploy at scale.