Docker: Entry into the world of containers

Docker: Entry into the world of containers

Docker's popularity has grown steadily in recent years. Applications are executed in a container and can therefore be "docked" in any environment. That sounds very exciting. But why should you be interested in that, is it even essential for development? Why is Docker such a revolution for us? Let's see and discover in this article.

Docker containers are encapsulated units that can be executed independently of one another, no matter where they are. Let's compare them to freight containers in which one or more males sit and work. And from a digital world, let's say these are applications such as PHP, MySQL, and Apache "stored" together in a container instead of men and cargo, which they work with. For the freight containers workers, it makes no difference whether the freight container is now in New York, Munich, or Sydney, since it always looks the same from the inside. Accordingly, the conditions are the same. The same applies to the applications in the software container.

Advantages of containers

The new technology is particularly popular with developers, because Docker containers are significantly more efficient and resource-saving than VMs: They require less CPU and memory.

Another advantage is its portability. As closed application packages, they can be executed on a wide variety of systems. This means that they can not only be used for offline development but also work on production servers without problems, regardless of the selected infrastructure or cloud platform. This results in higher speed and consistency in development, debugging, and testing.

Containers can be scaled up. For example, the traffic on a website increases as a result of a good marketing campaign - so with them it is easy to start and stop it.  This way, hundreds of containers can be moved up or down within seconds. The management of this large number can be made more accessible with orchestration solutions.

Containers are high on the list for digitization strategies with a focus on IT architectures. Containerization is considered the most significant change in the IT world since the introduction of hardware virtualization with virtual machines (VMs). This new variant of virtualization received its upswing with the trend towards so-called microservices and away from monolithic applications.

Similar to VMs, containers are a kind of storage for applications in which they can run. However, while VMs represent an entire computing environment, docker only contains the vital data required to run the application. This includes operating system components such as libraries and binaries. It makes the virtualization run in a lighter form. The best-known container technology is Docker, which is why the term "Docker Container" is on everyone's lips.

Other advantages are:

• good scalability through many other containers usage

• easy management of many containers using orchestration tools such as Kubernetes

• the quick start of containers.

We looked at the Docker Engine, which is embedded in a vast ecosystem around the containers. Now we know what Docker is and how to interact with it, knowing its advantages.