Registries

The four commands that make up the Docker Hub workflow, and how to decode the ‘denied: requested access’ error.

A tag is a mutable pointer to an image digest. Understanding that one fact explains most tagging mistakes.

A repository is a named bucket of related image versions. Here’s how naming, namespaces and visibility actually work.

A registry is just a content-addressed blob store with an HTTP API in front of it. Here’s how the pieces fit together.