Comprehensive Docker Tutorial: Installation, Image Management, Container Operations, and WordPress Deployment

Docker, first released in 2013, is a widely adopted container platform that isolates applications and their dependencies in lightweight, portable environments, addressing the long‑standing "environment configuration" problem in software development.

Unlike full virtual machines, containers share the host kernel, offering faster startup, lower resource consumption, and smaller image sizes. Docker images are binary templates that can be versioned, shared via Docker Hub, and instantiated as running containers.

Installation varies by OS; the tutorial lists official links for macOS, Windows, Ubuntu, Debian, Fedora, and other Linux distributions. After installing, verify with $ docker version or $ docker info . Users should add themselves to the docker group to avoid repeated sudo usage.

Key Docker commands are demonstrated: $ docker image ls lists images, $ docker image pull library/hello-world pulls an image, $ docker container run hello-world runs a container, and $ docker container rm [containerID] removes stopped containers. The --rm flag can automatically delete containers after they exit.

To build custom images, a .dockerignore file excludes unnecessary files, and a Dockerfile defines the build steps. An example Dockerfile for a Node.js Koa demo includes FROM node:8.4 , COPY . /app , WORKDIR /app , RUN npm install , EXPOSE 3000 , and optionally CMD node demos/01.js . Building and running the image uses $ docker image build -t koa-demo . and $ docker container run -p 8000:3000 -it koa-demo /bin/bash .

Publishing images involves tagging with a Docker Hub username ( $ docker image tag koa-demo:0.0.1 username/koa-demo:0.0.1 ) and pushing with $ docker image push username/koa-demo:0.0.1 .

The tutorial then shifts to a practical WordPress deployment scenario, presenting three approaches:

Method A – Build a custom WordPress container using a PHP image, mount the host directory, and link to a MySQL container.

Method B – Use the official wordpress image, link it to a MySQL container, and expose ports for stable access.

Method C – Define both services in a docker-compose.yml file, allowing a single docker-compose up command to start MySQL and WordPress together.

Each method includes detailed commands for creating containers, setting environment variables (e.g., MYSQL_ROOT_PASSWORD , WORDPRESS_DB_PASSWORD ), mapping volumes, and configuring port forwarding. The tutorial also covers stopping, restarting, and cleaning up containers and images.

Additional useful commands are listed, such as docker container start , docker container stop , docker container logs , docker container exec , and docker container cp , providing a full toolbox for container lifecycle management.

References to official documentation, source repositories, and further reading are provided at the end of the article.