Fundamentals of Docker containers

A form of container technology has existed in the Linux kernel since the 1970s. The technology powering today's containers, called cgroups, was introduced into the Linux kernel in 2006 by Google. The Docker company popularized the technology in 2013 by introducing an easy developer workflow. The company gave its name to the technology, so the name Docker can refer to both the company as well as the technology. Most commonly though, we use Docker to refer to the technology.

Docker as a technology is both a packaging format and a container runtime. We refer to packaging as an architecture that allows an application to be packaged together with its dependencies, such as binaries and runtime. The runtime points at the actual process of running the container images.

You can experiment with Docker by creating a free Docker account at Docker Hub (https://hub.docker.com/) and using that login to open Docker Labs (https://labs.play-with-docker.com...