As a programming language, Docker has its own “Hello World” container to test a basic container usage.
In order to use it, just run in your bash:
A couple of actions happened. What happened here in details:
You ran in your console
docker run command to run a named container
This container was not available in locally your host and thus Docker pulls last version of the image from Docker Hub registry. More details about pull action will be explained in other article.
This image is available in Docker Hub
Docker downloads image layers and creates your container. As you invoked
docker run, it runs the executable (this is a simple executable that prints on the screen).
If you run again, the image won’t be pulled again: