juniorDocker

What is Docker Hub?

Updated Apr 28, 2026

Short answer

A cloud-based registry service that allows you to link to code repositories and build, test, and store your Docker images.

Deep explanation

Docker leverages Linux namespaces and cgroups to provide isolation. Unlike VMs, there is no hypervisor layer overhead, allowing for near-native performance and rapid startup times.

Real-world example

A developer wants to ensure their app runs exactly the same on their laptop as it does on a colleague's machine.

Common mistakes

  • Confusing 'EXPOSE' with port publishing ('-p').

Follow-up questions

  • What is a 'layer' in Docker?

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