Hands-On Reactive Programming with Python

How images are composed together

Before running the full stack, let's talk a little bit about how images depend on each other. Docker is designed so that images can share common parts instead of duplicating them. This saves disk space, and avoids downloading the same files multiples times. It relies on a simple principle: an image is a filesystem packaged in a file. An image inherits from another image (or nothing, for root images); this means that a new image contains all the files of its parent image. New files are the only ones being stored in the new image. With this principle, only the differences from parent images must be stored on each image. Moreover, many different images can share the content of common parent images.

Technically, ...