===== Install in Linux =====
1. open https://get.docker.com

2. at the start of script there's section "This script is meant for quick & easy install via:" - just run 
these 2 commands (curl -fsSL get.docker.com -o get-docker.sh && sh get-docker.sh) and they will install //edge// version by default, adding repository for your distribution.

3. Add user to docker group:
   sudo usermod -aG docker user

4. Re-login to be applied to docker group   

5. Install //Docker Machine// from https://github.com/docker/machine/releases/, scroll to Installation -> On Linux and run commands:
   $ curl -L https://github.com/docker/machine/releases/download/v0.13.0/docker-machine-`uname -s`-`uname -m` >/tmp/docker-machine &&
    chmod +x /tmp/docker-machine &&
    sudo cp /tmp/docker-machine /usr/local/bin/docker-machine
But make sure to get lines from github, using latest version    

6. Similar for //Docker Compose// on https://github.com/docker/compose/releases:
  sudo curl -L https://github.com/docker/compose/releases/download/1.18.0/docker-compose-`uname -s`-`uname -m` -o /usr/local/bin/docker-compose
  sudo chmod +x /usr/local/bin/docker-compose
But make sure to get lines from github, using latest version

7. Now let's check:
   docker-compose --version
   docker-machine  --version
   docker version
Everything should work and no errors shown

8. Once a month or two repeat steps 5 and 6 to update docker compose and docker machine.