At begin, I would like to highlight that I have some experience with docker containers, I am aware of the fact that containers is not virtual machine and that the difference is huge, I know also that docker containers are simply processes enclosed in namepsaces and cgroups. 

However, yesterday I have read about something like:  

`docker-machine create --driver virtualbox containerhost` 

I was able to understand that it is strictly connected to `docker swarm` stack, however I would like to understand how does it work in details. To make this issue more clear I will ask specific questions: 

1. Can we create virtual machine using tool `docker-machine` ? If yes, what system will be chosen ? Can we ssh to this machine ?
2. Despite the fact I have never used `docker-machine` after typing `docker-machine ls` I can see one machine. What is it ?