To validate Docker has been installed correctly, let's run our first container, hello-world is actually an image, an image is an immutable snapshot of a container. Once we start these with the following command they become containers, think of it like types and instances, a type defines fields and methods making up behavior. An instance is a living instantiation of this type, you can assign other types to the fields and call the methods to perform actions.
$ docker run --rm hello-world
The first thing you should see is:
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
c04b14da8d14: Pull complete
Digest: sha256:0256e8a36e2070f7bf2d0b0763dbabdd67798512411de4cdcf9431a1feb60fd9
Status: Downloaded newer image for hello-world:latest
When you execute a docker run the first thing the engine does is check...