website/content/en/docs/reference/glossary/docker.md

---
title: Docker
id: docker
date: 2018-04-12
full_link: https://docs.docker.com/engine/
short_description: >
  Docker is a software technology providing operating-system-level virtualization also known as containers.

aka:
tags:
- fundamental
---
Docker (specifically, Docker Engine) is a software technology providing operating-system-level virtualization also known as {{< glossary_tooltip text="containers" term_id="container" >}}.

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Docker uses the resource isolation features of the Linux kernel such as cgroups and kernel namespaces, and a union-capable file system such as OverlayFS and others to allow independent containers to run within a single Linux instance, avoiding the overhead of starting and maintaining virtual machines (VMs).