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Docker Introduction

What is Docker ? 

Docker is an open source tool which can be majorly used for automating the deployment of applications . 
It helps to build, ship and run the application faster. It can be managed in same way any application. 
Dockers are comparatively lightweight containers which help them to be turn usable quickly. 

As Docker helps to package , ship and run an application in isolated environment in a secure way which helps to run multiple containers  simultaneously.



What is Docker Engine ? 
Docker Engine is an application which follow client-server architecture as show in below image


Docker Engine - A client server architecture with Objects
Docker Engine - A client server architecture app

Docker CLI ( Command Line Interface) the outermost layer is the client which uses Rest API to interact with the Docker Server( Inner most Layer) which is a daemon service . The interaction can be through direct commands from the command line or from a script . 

Docker Daemon serves the request . It also manages four objects using which it serves request : Storage, Images, Network, Container.
The daemon can also talk to other daemons to manage the various services of Docker. 
                                     

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