We will first understand how Docker builds and stores images and how these images are used by containers. Finally, you’ll need a short introduction to the technologies that enable both images and container operations.
A Docker image is built up from a series of layers. Each layer represents an instruction in the image’s Dockerfile
A storage driver handles the details about the way these layers interact with each other. Different storage drivers are available, which have advantages and disadvantages in different situations.
By default, docker stores everything in
ls /var/lib/docker on the docker host.