Docker for Beginners

Learn Docker from scratch.

What is Docker?

Docker is a platform for building, shipping, and running applications in containers.

Installation

Install Docker Desktop from docker.com.

Basic Commands

# Build an image
docker build -t my-app .

# Run a container
docker run -p 3000:3000 my-app

# List containers
docker ps

# Stop container
docker stop <container_id>

Dockerfile

Create a Dockerfile for your application:

FROM node:18-alpine

WORKDIR /app

COPY package*.json ./
RUN npm install

COPY . .

EXPOSE 3000
CMD ["npm", "start"]

Docker Compose

Orchestrate multiple containers:

version: '3.8'
services:
  app:
    build: .
    ports:
      - "3000:3000"
  db:
    image: postgres:15
    environment:
      POSTGRES_PASSWORD: secret

Conclusion

Docker simplifies application deployment and ensures consistency across environments.