About Virtualization

Virtualization means is creating the logical IT (Machines)resources, called virtual
system. Only one physical system (hardware,server).That's called system virtualization.
It's most commonly uses the Hypervisor for managing the resource for every virtual
system.The hypervisor is a software that can virtualize the hardware resources.

There are two types of hypervisors:

Type 1 hypervisor: Hypervisors run directly on the system hardware.
Type 2 hypervisor: Hypervisors run on a host operation system (windown xp, window 7, window 10, ubuntu desktop)that provides virtualization servers.

Type 1 hypervisors :-

1. VMware ESX and ESXi

There are some lower-cost bundles that VMware offers and they can make hypervisor technology more affordable for small infrastructures.

VMware is the leader in the Type-1 hypervisors. Their vSphere/ESXi product is available in a free edition and 5 commercial editions.

2. Microsoft Hyper-V

The Microsoft hypervisor, Hyper-V doesn’t offer many of the advanced features that VMware’s products provide.
However,  with XenServer and vSphere, Hyper-V is one of the top 3 Type-1 hypervisors.
It was first released with Windows Server, but now Hyper-V has been greatly enhanced with Windows Server 2012 Hyper-V. Hyper-V is available in both a free edition (with no GUI and no virtualization rights) and 4 commercial editions – Foundations (OEM only), Essentials, Standard, and  Datacenter. Hyper-V.

3. Citrix XenServer 

It began as an open source project.
The core hypervisor technology is free, but like VMware’s free ESXi, it has almost no advanced features.

Just as Red Hat Enterprise Virtualization uses KVM, Citrix uses Xen in the commercial XenServer.

4. Oracle VM

The Oracle hypervisor is based on the open source Xen.
However, if you need hypervisor support and product updates, it will cost you.
Oracle VM lacks many of the advanced features found in other bare-metal virtualization hypervisors.

Type 2 hypervisor :- 

1. VMware Workstation/Fusion/Player 

VMware Player is a free virtualization hypervisor.

VMware Player is a free virtualization hypervisor.
It is intended to run only one virtual machine (VM) and does not allow creating VMs.
VMware Workstation is a more robust hypervisor with some advanced features, such as record-and-replay and VM snapshot support.
VMware Workstation has three major use cases:

• for running multiple different operating systems or versions of one OS on one desktop,
• for developers that need sandbox environments and snapshots, or
• for labs and demonstration purposes.

2. VMware Server

VMware Server is a free, hosted virtualization hypervisor that’s very similar to the VMware Workstation.

3. Microsoft Virtual PC

This is the latest Microsoft’s version of this hypervisor technology, Windows Virtual PC and runs only on Windows 7 and supports only Windows operating systems running on it.

4. Oracle VM VirtualBox

VirtualBox hypervisor technology provides reasonable performance and features if you want to virtualize on a budget. Despite being a free, hosted product with a very small footprint, VirtualBox shares many features with VMware vSphere and Microsoft Hyper-V.

5. Red Hat Enterprise Virtualization

Red Hat’s Kernel-based Virtual Machine (KVM) has qualities of both a hosted and a bare-metal virtualization hypervisor. It can turn the Linux kernel itself into a hypervisor so the VMs have direct access to the physical hardware.

KVM

This is a virtualization infrastructure for the Linux kernel. It supports native virtualization on processors with hardware virtualization extensions.

Hypervisor that can be added to most Linux operating systems including Ubuntu, Debian, SUSE, and Red Hat Enterprise Linux, but also Solaris, and Windows.

Reference link.