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Hypervisor

What is hypervisor?
A hypervisor is a software that allows to run multiple virtual machines on a single hardware.

Types of hypervisor:
1. Bare metal hypervisor or type 1 hypervisor
Type 1 hypervisor are installed on the host hardware directly. Since there is no underlying software in the middle (between the hardware and hypervisor), these are faster and more efficient
Ex. VMWare ESX, Microsoft Hyper V, KVM (Kernel-based Virtual Machine)

2. Embedded hypervisor or type 2 hypervisor
Type 2 hypervisor are installed on the top of an existing operating system like Windows or Linux. Because of additional layer of management, these are considered less efficient compared to type 1 hypervisor. Also the additional layer poses security concern. Since they are installed on a hosted OS they are much easier to use.
Ex. VMWare Player, VirtualBox

So what hypervisors does Azure and Amazon use ?

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