Docker is an open-source platform that enables developers to build, deploy, run, update, and manage containers - standardized, executable components that combine application source code with the dependencies and libraries needed to run the code in any environment. Containers are isolated from one another and bundle their own software, libraries, and configuration files, and they can communicate with each other through well-defined channels). Docker containers are the live, running instances of Docker images, which are lightweight, standalone, executable packages of software that include everything needed to run an application: code, runtime, system tools, system libraries, and settings. Docker provides the ability to package and run an application in a loosely isolated environment called a container, which is lightweight and contains everything needed to run the application, so you dont need to rely on whats installed on the host. Docker is used to automate the deployment of applications in lightweight containers so that applications can work efficiently in different environments in isolation). Docker is installed on each server and provides simple commands that can be used to build, start, or stop containers. Docker is perfect for high-density environments and for small and medium deployments where you need to do more with fewer resources.