Please visit the Docker Hub, and see that what is there is known as Docker Image, and it is basically the skeleton of the container (model).
Docker Images are generated by Dockerfiles, and they contain all the information needed to create a container, in order to make it easy to maintain and customize.
If you look with attention into the Docker Hub, it’s easy to see that the PostgreSQL image, called postgres, have different tags and versions, and if you don’t specify one of them the default will be used, the latest, but maybe in the future if you need different containers of PostgreSQL working together, you may want them to be in the same version.
Let’s create our first right container now, remember the need for the argument ‘–network’, or it will be deployed in the default bridge.