Docker is a popular open‑source platform for running applications in “containers”, enabling developers to build and deliver code consistently across environments. Since its introduction in 2013 it has changed how we approach distributed systems and DevOps.
The platform includes tools like the Docker Engine (daemon + CLI), registries such as Docker Hub, Docker Desktop for local development and helpers like Compose and Swarm for orchestration. Everything centers on the idea that containers should be lightweight, portable and secure.
In practice you write a Dockerfile - a text file that describes how to build your application. Docker then produces an image you can run as a container with a single command. This brings repeatability to development and production, and makes it straightforward to scale and share applications.
Docker integrates well with orchestration and cloud platforms such as Kubernetes, AWS, Azure and Google Cloud, making it a natural fit for modern container-based workflows. A rich ecosystem of images, community tools and documentation makes it easy to get started and see results quickly.









































