Docker Engine overview

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Docker Engine is an open source containerization technology for building and containerizing your applications. Docker Engine acts as a client-server application with:

  • A server with a long-running daemon process dockerd.
  • APIs which specify interfaces that programs can use to talk to and instruct the Docker daemon.
  • A command line interface (CLI) client docker.

The CLI uses Docker APIs to control or interact with the Docker daemon through scripting or direct CLI commands. Many other Docker applications use the underlying API and CLI. The daemon creates and manage Docker objects, such as images, containers, networks, and volumes.

For more details, see Docker Architecture.

Docker user guide

To learn about Docker in more detail and to answer questions about usage and implementation, check out the overview page in “get started”.

Installation guides

The installation section shows you how to install Docker on a variety of platforms.

Release notes

A summary of the changes in each release in the current series can now be found on the separate Release Notes page

Feature Deprecation Policy

As changes are made to Docker there may be times when existing features need to be removed or replaced with newer features. Before an existing feature is removed it is labeled as “deprecated” within the documentation and remains in Docker for at least 3 stable releases unless specified explicitly otherwise. After that time it may be removed.

Users are expected to take note of the list of deprecated features each release and plan their migration away from those features, and (if applicable) towards the replacement features as soon as possible.

The complete list of deprecated features can be found on the Deprecated Features page.


Docker is licensed under the Apache License, Version 2.0. See LICENSE for the full license text.