Difference between Running and Starting a Docker container

Question

In practice to start a container I do:

docker run a8asd8f9asdf0

If thats the case, what does:

docker start         


        

Answer 1

• run runs an image
• start starts a container.

The docker run doc does mention:

The docker run command first creates a writeable container layer over the specified image, and then starts it using the specified command.

That is, docker run is equivalent to the API /containers/create then /containers/(id)/start.

You do not run an existing container, you docker exec to it (since docker 1.3).
You can restart an exited container.