Docker tutorial: Get started with containers, images, and Compose

Learn what Docker is, how it solves environment differences, and how images, containers, registries, Docker Engine, and virtual machines fit together.

Install Docker on Windows with WSL 2, macOS, and Linux (Ubuntu 26.04 / 24.04). Verify virtualization and WSL, then test with docker version and hello-world.

A screen-by-screen tour of Docker Desktop, from the sidebar and container controls to logs, files, Compose projects, images, and the Docker commands behind each action.

Run your first Docker container with nginx: pull an image with docker run, open it in a browser, inspect it with ps, logs, and exec, and manage it with stop, start, and rm.

Learn Docker image names, tags, and digests, then use pull, images, tag, rmi, history, inspect, save, and load. Compare image sizes and layers.

Learn Docker container states, why containers exit, stop vs. kill, the 10-second stop timeout, exit codes, and restart policies with real output.

Learn the most useful docker run flags: -d, -it, -p, -v, -e, --name, --rm, --network, --restart, resource limits, and more, with real commands and output.

Learn to debug Docker containers with logs, exec, inspect, cp, stats, top, and diff, and troubleshoot common startup, port, and exec format errors.

Learn to write a Dockerfile with a Node.js example. Read docker build output, understand each instruction and build cache, and use .dockerignore to shrink the build context from 30 MB to under 1 KB.

Use docker init to answer a few questions and generate a Dockerfile, compose.yaml, .dockerignore, and README.Docker.md. See the full Node.js walkthrough, review each generated file, use docker build --check to find two template warnings, and learn where the PostgreSQL example fails with postgres:18.

Learn the most common Dockerfile instructions and see them in action: FROM, RUN, COPY, ADD, WORKDIR, ENV, ARG, EXPOSE, USER, VOLUME, HEALTHCHECK, CMD, and ENTRYPOINT. Compare CMD and ENTRYPOINT, COPY and ADD, ARG and ENV, and see how PID 1 affects docker stop.

Learn Docker build cache rules, how instruction order affects build time, how to reduce image size by cleaning in the same layer, and how to use cache mounts and clear the build cache.

Separate build and runtime environments with multi-stage builds. Compare Go image sizes and explore Dockerfile examples for Node.js, Java, and frontend apps.

Learn docker login, docker tag, and docker push to upload images to Docker Hub and GitHub Container Registry, and run a private Registry with registry:3.

Keep data after containers are removed. Learn Docker volumes, bind mounts, anonymous volumes, backup and restore, path behavior, and the PostgreSQL 18 data directory.

Learn how Docker networking works, connect containers by name on custom networks, publish ports, reach the host, and troubleshoot common connection issues.

Learn -e, --env-file, Dockerfile ENV, and Compose environment, env_file, and .env substitution with real output, plus safe ways to pass secrets.

Get started with Docker Compose: launch a website, PostgreSQL, and Adminer with one compose.yaml file. See real output for up, ps, logs, stop, and down, plus Adminer login, SQL, and how down -v affects data.

Learn the complete syntax of Docker Compose's compose.yaml file, including services, builds, ports, volumes, health checks, profiles, overrides, and validation.

A practical guide to Docker Compose commands: up, down, ps, logs, exec, run, pull, and config. See why restart does not apply compose.yaml changes and when to use up -d.

Set up WordPress 7 and MySQL 8.4 with Docker Compose. Configure health checks, persistent data, upload limits, phpMyAdmin, backups, restores, and image updates.

Package Python apps as Docker images with tested Flask, FastAPI, and Django examples, development reload, collectstatic, uv locks, and image size comparisons.

Build Node.js images with Docker: use npm ci, run as a non-root user, handle SIGTERM, build TypeScript apps, slim Next.js images, and reload code during development.

Serve static sites with Nginx in Docker, configure SPA fallbacks and caching, validate config, proxy to backend containers, troubleshoot 502 errors, and enable HTTPS with Caddy.

Run MySQL 8.4 in Docker with real output: environment variables, init SQL, utf8mb4, connecting from the container, host and other containers, localhost vs 127.0.0.1, the Compose health check trap, mysqldump backup and restore, and why a changed password variable has no effect.

Run PostgreSQL 18 in Docker with real output: its new data directory, Compose setup, pg_isready health check, psql commands, passwordless container access, backups, restores, and a 16-to-18 upgrade.

Run Redis 8 with Docker: use redis-cli, configure passwords, compare RDB and AOF persistence, test memory eviction, and connect a Flask app with Compose.

Is Docker using too much disk space? Find out with docker system df, then safely clean up containers, images, volumes, builder cache, and logs.

Learn Docker container security with hands-on examples: run as non-root, pin image versions, keep secrets out of layers, use BuildKit secrets, restrict ports and privileges, set resource limits, protect docker.sock, and scan and patch vulnerabilities with Trivy.

See how Rootless Docker maps container root to an unprivileged host user, blocks access to /etc/shadow, and compare it with daemonless Podman.

Image built on an Apple Silicon Mac fails on a server with exec format error? Learn CPU architectures and multi-platform images, build linux/amd64 and linux/arm64 at once with docker buildx and Go cross-compilation, inspect with docker images --tree, push and check the manifest, and know when you need QEMU.

Automatically build multi-platform Docker images and push them to GitHub Container Registry, then deploy to a server over SSH. Includes a complete workflow, tag rules, build cache, and actionlint validation.

Deploy a Docker app to a Linux cloud server with a complete walkthrough: build and push an image, run it with Compose, update and roll back, automate backups, and review a launch checklist.

See what a container is on a Docker host: a Linux process isolated by namespaces, limited by cgroups, and given a filesystem by overlayfs. Inspect PIDs, resource limits, image layers, and security controls.

Find the cause of Docker errors like daemon connection failures, permission denied, port conflicts, missing files, Compose health checks, and PowerShell issues, with real output and fixes.

A one-page guide to the Docker commands you use most: containers, images, builds, volumes, networks, Compose, cleanup, and system info, with concise explanations.

A complete guide to docker build options (-t, -f, --build-arg, --target, --no-cache, --pull, --platform, --progress, --secret, --check, -q, and more), with Docker 29 examples for naming images, passing build arguments, choosing a Dockerfile, building to a stage, and viewing full build output.

Learn every docker exec option, including -it, -u, -w, -e, -d, --env-file, and --privileged. Examples cover shells, users, directories, environment variables, background tasks, and stopped containers.

Learn docker ps options: list all containers, filter by status, name, or label, customize output, show sizes, and remove stopped containers. Includes Docker 29 examples.

A complete guide to docker logs options (-f, -n/--tail, -t, --since, --until, --details), with Docker 29 examples for filtering, timestamps, stdout and stderr, grep, and following new logs.

Learn docker cp syntax and how to copy files and folders between containers and hosts, handle missing files, and back up or restore databases on Windows.

Learn Docker inspect options and Go templates with real Docker 29 examples for container state, IPs, environment variables, image details, volumes, networks, and the removed IPAddress field.

A complete guide to docker volume create, ls, inspect, rm, and prune, with hands-on Docker 29 examples for writing data, finding dangling anonymous volumes, labels, and prune versus prune -a.

A complete guide to the docker network create, ls, inspect, connect, disconnect, rm, and prune commands, with examples tested on Docker 29.

Learn `docker compose up` options including `--build`, `--wait`, `--scale`, and `--exit-code-from`, with practical Docker Compose v5 examples.

Learn docker compose down options, including -v, --rmi, --remove-orphans, and --timeout, with examples and the differences between down, stop, and rm.