Getting to grips with Docker
As we learned from the introduction, Docker containers use shared operating systems. This means a much more efficient usage of system resources compared to Virtual Machines. The following diagram summarizes the concepts exposed so far, giving you an idea of the infrastructure of containers compared with VMs:
As you can see from the preceding diagram, instead of virtualizing hardware, containers rest on top of a single host operating system. This in turn, means that you can leave behind all the unneeded VM features, leaving you with a small, neat capsule containing your applications.
Basic components of containers
In order to get started with Docker, it is important to have a solid grasp of the main components that make up the Docker ecosystem. In detail, Docker is composed of the following elements:
- Images: A Docker image is, in a nutshell, an immutable file which contains some software such as operating systems, databases, or application servers. Images can...
