title: docker: unrecognized service
body: <p>I am getting this error while running</p>
  <pre><code>&gt;service docker start                                                       
  docker: unrecognized service
  &gt;service docker.io start                                                    
  docker.io: unrecognized service
  </code></pre>
  <p>I am struggling with docker in order to run it. I got <code>Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?</code> error. thereafter I tried several things but it did not work.</p>
  <pre><code>&gt;docker pull pstothard/cgview                                               
  Using default tag: latest                                                                                      
  Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
  
   &gt;sudo docker run hello-world                                                
   docker: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?.
  
  &gt;systemctl start docker.service                                             
  System has not been booted with systemd as init system (PID 1). Can't operate.
  
  &gt;docker images                                                             
  Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: 
  Get http://%2Fvar%2Frun%2Fdocker.sock/v1.40/images/json: dial unix /var/run/docker.sock: connect: permission denied 
  
  &gt;snap stop docker                                                           
  Interacting with snapd is not yet supported on Windows Subsystem for Linux.                                      
  This command has been left available for documentation purposes only.
  </code></pre>
  <p>I'm using ubuntu 18.04 app in windows system. what should I do?</p>