What is Port Binding?

Port Binding = Connecting container's internal port to your computer's port so you can access the app.

Think of it:

• Container = House with door number (port 5000)
• Your PC = Street with address (port 8080)
• Port binding = Creating a pathway between them

Without Port Binding ❌

docker run my-app

Problem:

• App runs on port 5000 inside container
• You cannot access it from browser
• It's isolated!

With Port Binding

bash

docker run -p 8080:5000 my-app
#           ↑    ↑
#       Your PC : Container

Now:

• App runs on port 5000 inside container
• Accessible at http://localhost:8080 on your PC