Docker and Its components

Docker:
Docker is a tool/system/framework designed to make it easier to create, deploy, and run applications by using containers.
Containers allow a developer to package up an application with all of the parts it needs, such as libraries and other dependencies, and ship it all out as one package.


Docker Components:
Images - The blueprints of our application which form the basis of containers. 

Containers - Created from Docker images and run the actual application. We can create a container using docker run.

Docker Daemon - The background service running on the host that manages building, running and distributing Docker containers. 
The daemon is the process that runs in the operating system to which clients talk to.

Docker Client - The command line tool that allows the user to interact with the daemon. More generally, there can be other forms of clients too - such as Kitematic which provide a GUI to the users.

Docker Hub - A registry of Docker images. You can think of the registry as a directory of all available Docker images. If required, one can host their own Docker registries and can use them for pulling images.