Docker container image format

Docker revolutionized container image management when it solved the container image de-duplication problem with hashed and overlayed images. During each step of a build, a checksum is generated for the image. If more than one image shares a layer or group of files, then there is no need to store them multiple times. This is a much more efficient way to store artifacts with shared dependencies compared to LXD containers.

Docker donated quite a bit of core technology to the CNCF foundation, with the container image format being part of the Container Native Initiative. A lot of traditional Docker containers you may be familiar with are now considered version 1, with version 2 extending a backward-compatible extension of version 1. Version 2 has become the standard for OCI projects, including Podman and newer releases of Docker. Note that a Podman builder is available as an external plugin that is based on the Docker plugin. Podman was built using Cgroups...