if you use the os centos and don't think about inner process
just write the follow the line
$ su - root
$ curl -fsSL https://get.docker.com/ | sudo sh
if you encounter this message "cannot connect to the docker daemon at //var/run/docker.sock.
is the docker daemon running?" you didn't start the docker daemon.
$ sudo systemctl start docker
$ sudo systemctl enable docker
otherwise, you read the website
https://docs.docker.com/install/linux/docker-ce/centos/
followed added lines are parts of website
$ sudo yum install /path/to/package.rpm
Docker is installed but not started. The docker
group is created, but no users are added to the group.
Start Docker.
$ sudo systemctl start docker
Verify that Docker Engine - Community is installed correctly by running the hello-world
image.
$ sudo docker run hello-world
https://docs.docker.com/docker-for-windows/
https://docs.docker.com/docker-for-mac/