Docker enables you to separate your applications from your infrastructure so you can deliver software quickly. Docker streamlines the development lifecycle by allowing developers to work in **standardized environments using local containers** which provide your applications and services.

What is Docker?

Difficulty: 5/10

container lifecycle, image management, deployment pipelines

Docker is a tool that packages software and its dependencies into a container so it can run reliably on any system.

1
Docker enables you to separate your applications from your infrastructure so you can deliver software quickly.
2
Docker streamlines the development lifecycle by allowing developers to work in standardized environments using local containers which provide your applications and services.

Scenario Questions

0-2 years experience

1How would you use Docker to run a simple Node.js app locally for development?
2If you build a Docker image and then run a container, but the app inside can't connect to the host's database, what might be wrong?
3What command would you use to see which ports a container is exposing, and why is that important?

Follow-up Questions

Can you walk me through the exact Docker commands you'd use for that task?
What metrics would you monitor to verify your solution works in production?
How would you address a scenario where the container image size becomes a bottleneck?