What is Docker Hub?

Docker Hub is the world's largest public container registry where developers store and share Docker images. It is the default registry Docker uses when you run docker pull.

Think of Docker Hub like GitHub but for Docker images.

Docker Hub Features

• Free public repositories for open-source images
• Official images for Nginx, MySQL, PHP, Node.js, Ubuntu
• Private repositories (limited on free plan)
• Automated builds from GitHub/Bitbucket
• Image versioning with tags

Push Your Image to Docker Hub

Step 1: Create a Docker Hub Account

Visit https://hub.docker.com and create a free account.

Step 2: Login from Terminal

docker login

Enter your Docker Hub username and password.

Step 3: Build and Tag Your Image

docker build -t my-app .
docker tag my-app yourusername/my-app:v1.0

Step 4: Push Image to Docker Hub

docker push yourusername/my-app:v1.0

Step 5: Pull Image on Another Machine

docker pull yourusername/my-app:v1.0
docker run -d -p 8080:80 yourusername/my-app:v1.0

Using Official Images from Docker Hub

docker pull nginx:latest
docker pull mysql:8.0
docker pull php:8.2-apache
docker pull node:18-alpine
docker pull ubuntu:22.04

Searching Images on Docker Hub

docker search nginx

Output:

NAME           DESCRIPTION                 STARS
nginx          Official build of Nginx     18000+
bitnami/nginx  Bitnami nginx Docker image  150+

Setting Up a Private Registry

# Run local private registry on port 5000
docker run -d -p 5000:5000 --name registry registry:2

# Tag image for private registry
docker tag my-app localhost:5000/my-app

# Push to private registry
docker push localhost:5000/my-app

# Pull from private registry
docker pull localhost:5000/my-app

Docker Hub vs Private Registry

Summary

• Docker Hub is the default public registry for Docker images
• Use docker login, docker tag, and docker push to publish your images
• Pull official images like Nginx, MySQL, PHP directly from Docker Hub
• For enterprise use, set up a private registry with AWS ECR or self-hosted