What is Docker?

Before we begin to work with Docker, let's have a look at exactly what Docker is. If you head on over to https://www.docker.com and look at the What is Docker? page, you will see that they say that Docker is a containerization platform. From a first-look perspective, this does not make much sense. Digging a little deeper though, you will see that Docker simplifies the application-building process and allows you to ship and run those applications in different environments. The different environments may be development, testing, user acceptance testing, and production environments.

Docker makes use of images and containers, and if you look at the Docker logo, you will see this idea of containers represented in their logo:

Cargo planners often have to be very careful how they stack the containers on a cargo ship. They need to keep the container destinations in mind when planning the location of the container on the ship.

For example, a container bound for the Middle East could...