Master Docker from Zero: Build, Run, and Deploy Containers Like a Pro

1. Story

To illustrate Docker, imagine building a house, then using a magic spell to create an image that can be copied and deployed elsewhere, just like container images.

Build once, run anywhere!

2. Virtual Machines vs Containers

Virtual machines emulate full hardware and are heavier, while containers virtualize the operating‑system layer, offering lightweight, fast, and resource‑efficient isolation.

VMs are larger, slower to start, and consume more resources.

Containers share the host OS kernel, start quickly, and use far less disk space.

Containers are a lightweight form of virtualization.

3. Understanding Docker

Docker is an open‑source container engine that packages applications and their dependencies into portable images. Its three core concepts are Image, Container, and Repository.

4. Core Concepts

Build

, Ship,

Run

Build once, Run anywhere

Docker creates containers; it is not a container itself.

Docker uses Linux kernel features such as cgroups and namespaces.

Images contain code, runtime, libraries, environment variables, and configuration; containers are runtime instances of images.

5. Installing Docker

On macOS you can install via Homebrew Cask: brew cask install docker Check the version: docker -v Configure registry mirrors by editing /etc/docker/daemon.json:

{
  "registry-mirrors": [
    "http://hub-mirror.c.163.com/",
    "https://registry.docker-cn.com"
  ],
  "insecure-registries": [],
  "experimental": false,
  "debug": true
}

6. Quick Start

Create a Vue project, build it, and write a Dockerfile that copies the dist folder into an Nginx image:

FROM nginx
COPY dist/ /usr/share/nginx/html/
COPY default.conf /etc/nginx/conf.d/default.conf

Build the image: docker build -t jartto-docker-demo . Run the container:

docker run -d -p 3000:80 --name docker-vue jartto-docker-demo

7. Common Dockerfile Instructions

FROM : base image.

MAINTAINER : image author.

RUN : commands executed during build.

ADD : copy files and optionally extract archives.

COPY : copy files without extraction.

CMD : default command when container starts.

ENTRYPOINT : command that cannot be overridden.

LABEL : metadata.

ENV : environment variables.

EXPOSE : ports to expose.

VOLUME : mount points for persistent data.

WORKDIR : working directory.

USER : user to run commands.

ARG : build‑time variables.

8. Best Practices

Specify exact images you need.

Keep Dockerfile steps minimal and ordered.

Tag images with clear version numbers.

Document the build process for reproducibility.

9. Conclusion

Containerization is essential in the cloud era; Docker is just the beginning, leading to orchestration tools like Kubernetes, Service Mesh, and Istio.