beginnerDocker Architecture, Engine, Daemon, Client & Registry

What is the OCI and why does it matter?

The Open Container Initiative defines open specifications for container images (image-spec) and runtimes (runtime-spec). Because Docker images conform to OCI image-spec, they are portable: an image built by Docker can run unmodified under containerd, CRI-O, or Podman. This is why Kubernetes can drop Docker entirely yet still run 'Docker images'.

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