Docker Tutorial for Beginners – Learn Docker, Dockerfile Tutorial & Docker Compose

Docker Tutorial Summary & Core Concepts

Docker helps you build images and run containers consistently across environments — ideal for beginners learning the docker basics and anyone who wants a practical docker guide.

Core Concepts (docker container basics)

• Image — a “recipe” with base runtime, dependencies, and commands.
• Container — a running instance of an image where your code executes.

Install Docker (Windows)

1. Download and install Docker Desktop.
2. Verify installation:

   docker --version

   Copy
3. Open VS Code and install the Docker extension.

Work with Docker (learn docker)

# Base image: Node.js v22
FROM node:22
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
ENV PORT=9000
EXPOSE 9000
CMD ["npm","start"]

docker build -t test .

docker run -p 9000:9000 test

Docker Compose Tutorial (docker compose up)

If your app has multiple parts (backend + database), manage them together with Docker Compose.

Typical Problems

• Starting each container manually is tedious.
• Wiring containers together (network/ports/env) is error-prone.

Solution: compose.yaml

services:
  backend:
    build: .
    ports:
      - '9000:9000'
  db:
    image: postgres:latest
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: pass
      POSTGRES_DB: mydb
    volumes:
      - postgres_data:/var/lib/postgresql/data

volumes:
  postgres_data:

Compose Commands

docker compose up

docker compose down

Docker Build Cloud

• Cloud builds can be faster than local builds.
• Teams can share build caches to speed up CI pipelines.

Quickstart

docker init

Docker scaffolds the necessary files (Dockerfile, compose file).