While using Docker command lines, I found it’s sometime a bit confusing to deal with containers. For the underlying operating system, a container is like a process. That is why the docker command use “ps” as the command to list these commands.
However, the typical “ps” command lists all the running processes. When a process dies, it is gone and there is no need to list it at all. For the containers, the story is different. The container can also be stopped, paused, which is different from running state. But you can still bring them back to running state later.