Docker Essentials

Images vs containers

The single most important distinction in Docker, explained with a class-and-object analogy and real commands.

Everyday container commands

Logs, exec, inspect, and the debugging workflow you'll use on every container you ever run.

Writing your first Dockerfile

Every Dockerfile instruction explained line by line, building a real Node.js app image from scratch.

Multi-stage builds

How to keep production images small by separating build-time tools from what actually ships.