Difference between Docker (Container) and Virtual Machine (Hypervisor)

Introduction

Often we keep getting confused as to why use one over another.

What are the actual differences! 

So I have tried to consolidate some of the basic differences in this blog.

Type	Docker (Container)	Virtual Machine
Behavior of application Run	Isolated	Isolated
Libraries Needed (example: curl, glibc)	Uses it's own	Uses it's own
Kernel	Host's kernel	Own kernel
Operating System (OS)	Host's OS	It's own OS acting as Guest OS

Docker kernel is same as Host's kernel?

Since all Linux distribution's use same underlying Linux Kernel and only differ in their user view (view can be UI or application software's). It is pretty easy to add different user view over another Linux OS kernel.

That's the main reason an OS on top on another OS is usually the case for virtual machine.

Due which, we cannot run FreeBSD or Windows via docker.

Container vs Virtual Machine

Now if you closely observe, in case of VM, we have every VM with their own Operating System, but docker is light weighted which uses the underlying OS's kernel and get's to facilitate a simulation as if it is a OS on itself.

Usecase of VM: Windows host with Ubuntu VM

Usecase of Docker: Ubuntu host with Redhat Docker

Another image

VM: Own kernel and hardware requirements like, RAM and CPU utilization.

Docker: Uses kernel and hardware of Host machine.

Thank's For Sticking By! :)

Disclaimer: Images shown in this post is picked from online image repository and not claiming any ownership of the same.