Brief Docker Intro

Three core concepts to use docker effectively: 1) Understanding the difference between images and containers, 2) understanding how to share files between the docker host and a container, 3) understanding how to map network ports from the docker host to the container. youtube

Like many computer tools, what really makes the tool useful is when humans develop their own mental model of how the tool works.

Practice helps build those mental models.

See Wiki in Docker

See Why Containers Work

On reflection, I didn't in this video explain the difference between images and containers very well. I think that content must have been lost in the revisions I made of this video.

Images are a like a frozen ecosystem for unix programs. They hold the program and a collection of resources the program needs to run effectively.

When we launch a container, it is a bit like we have thawed a copy of the frozen ecosystem. Now in the thawed form the program can go about its behavior in a friendly environment where it can find all the things it needs.

Images are frozen. Containers are alive.

Our programs need to be able to interact with the outside world.