🐳Docker Containers Basics
Build the mental model first, then the commands — from containers vs VMs through images, layers, volumes, and networking to composing a multi-service app.
Phase 1Containers Under the Hood
Understand what containers actually are under the hood
A container is a process, not a machine
6 minA container is a process, not a machine
An image is a recipe, a container is tonight's dinner
6 minAn image is a recipe, a container is tonight's dinner
Every Dockerfile line is a snapshot you can reuse
7 minEvery Dockerfile line is a snapshot you can reuse
Five commands cover 90% of your Docker day
7 minFive commands cover 90% of your Docker day
Phase 2Dockerfile Craft
Write Dockerfiles for real app types
Serve a static site in four lines of Dockerfile
6 minServe a static site in four lines of Dockerfile
Your node_modules don't belong in the image (mostly)
7 minYour node_modules don't belong in the image (mostly)
Build in one image, ship in another
7 minBuild in one image, ship in another
Virtual environments inside containers are redundant (usually)
6 minVirtual environments inside containers are redundant (usually)
Your .dockerignore is as important as your Dockerfile
6 minYour .dockerignore is as important as your Dockerfile
Phase 3Registries, Networks, and Volumes
Wire up registries, networks, and persistent storage
Docker Hub is git push for your containers
7 minDocker Hub is git push for your containers
Containers can't talk to each other by default
7 minContainers can't talk to each other by default
Containers forget everything when they die
7 minContainers forget everything when they die
Configuration lives outside the image, always
7 minConfiguration lives outside the image, always
Phase 4Compose a Multi-Service App
Containerize and compose a multi-service app
One YAML file to rule your entire stack
8 minOne YAML file to rule your entire stack
Frequently asked questions
- What's the difference between an image and a container?
- This is covered in the “Docker Containers Basics” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- How does layer caching work?
- This is covered in the “Docker Containers Basics” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- When should I use multi-stage builds?
- This is covered in the “Docker Containers Basics” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- How do Docker volumes persist data?
- This is covered in the “Docker Containers Basics” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
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