title: Docker container's image name issue
body: <p>I am running Docker version 17.12.1-ce.</p>
  
  <p>I have a confusion with naming and setting names of containers and/or images.</p>
  
  <p>I do not know how to set the IMAGE name to be displayed as wanted.</p>
  
  <pre><code>$ docker ps -a
  CONTAINER ID        IMAGE                COMMAND                  CREATED             STATUS                    PORTS                    NAMES
  a940a1fc8cd6        eaa0022f09d0         "/bin/sh -c 'set -ex…"   15 hours ago        Exited (4) 15 hours ago                            psql-Base-test-1
  78f14cde1e83        mycomp/postgres:10   "docker-entrypoint.s…"   8 weeks ago         Up 6 weeks                0.0.0.0:5402-&gt;5432/tcp   psql-Base-test-2
  </code></pre>
  
  <p>I want the image <strong>eaa0022f09d0</strong> also give a speakable/readable name like <strong>mycomp/postgres:9.6</strong>.</p>
  
  <p>When I take a look at the images it looks properly set up:</p>
  
  <pre><code>$ docker images
  REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
  mycomp/postgres     9.6                 eaa0022f09d0        15 hours ago        37.8MB
  mycomp/postgres     10                  46f8aa84d854        8 weeks ago         666MB    
  </code></pre>
  
  <p>Do I need to start a container from an image before the naming takes place properly?</p>
  
  <p>One confusion issue for me is how the <strong>IMAGE</strong> column on <em>docker ps</em> command is connected to an image listed by <em>docker images</em>. It seems not to be necessarily the <strong>IMAGE ID</strong> but rather sometimes a mix from <strong>REPOSITORY</strong> and <strong>TAG</strong> and <strong>IMAGE ID</strong>.</p>
  
  <p>Can someone share my confusion or enlighten me?
  As I see I successfully managed it like half a year ago but now consuion grew...</p>