Docker Explained: What It Is and How It Works

Introduction

Docker has changed how developers build, ship, and run applications by packaging code and dependencies into portable containers.

$ docker run hello-world

In this article, we'll explore what Docker is, how it works under the hood, and why it became such a common tool in modern development workflows.

What is Docker?

Docker is an open platform for developing, shipping, and running applications in containers. A container wraps an application with the runtime, libraries, and configuration it needs.

Build once, run anywhere.

This consistency helps teams avoid environment drift between local machines, staging, and production servers.

How It Works

Docker uses a client-server architecture. The Docker client talks to the Docker daemon, which builds images, runs containers, and manages their lifecycle.