Introduction to Containers

Docker implements the Open Container Initiative (OCI) specifications. This means some of the things you’ll learn in this chapter will also apply to other container runtimes and platforms that implement the OCI specifications.

Docker containers: A quick overview

Containers are runtime instances of images, and we can start one or more containers from a single image. The figure below shows multiple containers started from a single image. The shared image is read-only, but you can write to the containers.