Virtual Machines (VM)

A server is nothing but a where you deploy your application for end users or customers that is known as a public server.
For example, we access google.com so that google.com is deployed on a public server.

We used the server that is known as the physical server.
Configuration or specification of those servers had been very high and that was also very costly.
And we were just able to run one application only on one server. we could not run two or more applications on one or a single server.
And after running one application on one server, we were not able to use our resources very efficiently.
That's how "Virtualization" comes into the picture.

It is a technique of splitting physical resources into as many logical resources as we want example: CPU, and memory.

Hypervisor is a piece of software or firmware that creates and runs virtual machines.
A hypervisor is sometimes also called a VM manager.

Two types of hypervisors are there:-
1.) Bare metal hypervisor: This kind of hypervisor is directly hosted on hardware, that's why known as a bare metal hypervisor.
Sometimes they are also known as type 1. and generally organizations used this kind of hypervisor.
It has direct access to hardware and resources.
Examples: Microsoft Hyper-V, VMware ESXi and others.
2.) Hosted hypervisor: This kind of hypervisor is hosted on an Operating system (OS).
Also known as type 2. use case: for testing and learning purposes.
Example: VM ware workstation and others.