Hi,
For those of you wondering what the heck does this mean practically, gonna post several easy to follow examples, that will only require a web browser 
UPDATE:
Check out the following post below for easy 1 click docker demos:
OpenEMR Official Docker has been released!
There is this very cool website at labs.play-with-docker.com (11/23/17 edit: you now need to login to use this site; you need to create an account at https://hub.docker.com/ and then use these credentials to log into labs.play-with-docker.com) where you can basically run and deploy dockers, which is good place to showcase dockers.
The first example is where you can click on the below long link and the above website will build and deploy the OpenEMR docker for you to try it out. It uses a docker-compose.yml file which is a higher level mechanism to deploy docker stacks and feeds it directly to labs.play-with-docker.com .
http://play-with-docker.com/?stack=https://gist.githubusercontent.com/bradymiller/988d5105e38ffd8f6fb3cf49bbfae9f0/raw/26fa8e7e3e1d7cd97d60185a96a033cff33df346/openemr-500-docker-example-docker-compose.yml
After a couple minutes, it will be complete. And if you then click on the ‘80’ button near the top, this will open a window into the already installed/configured OpenEMR.
If you are curious, click the *_node1 box at left below the Add New Isntance and it will open the shell to where the dockers you deployed are. Then type ‘docker ps -a’ at the command prompt, and you’ll see a docker for mysql and openemr, which are the containers. The images (which are where the containers come from) can be viewed with ‘docker images’.
until the next cool example(4 lines of code to bring in docker stack for mysql, phpmyadmin, and openemr),
-brady