The Cloud and Virtual Worlds - Cloud & Virtualization Basics

Creating Machines from Software: What is Virtualization? (Hypervisors, Virtual Machines)

Virtualization is the process of creating a virtual, software-based representation of something physical, such as a server, storage device, or network. In the context of servers, it allows you to run multiple separate "computers" on a single piece of physical hardware.

• How It Works: The Hypervisor

  Virtualization is made possible by a special type of software called a hypervisor. The hypervisor is a lightweight software layer that sits between the physical hardware and the virtual machines. Its job is to abstract the hardware resources (CPU, RAM, storage) and allocate them to multiple independent virtual environments.

  • Analogy: Think of a physical computer as a large, empty house. The hypervisor is the building manager who comes in and divides the house into several self-contained apartments, each with its own walls, plumbing, and electricity.

• Virtual Machines (VMs)

  A Virtual Machine (VM) is the digital replica of a physical computer. Each VM is a self-contained, isolated software container that runs its own complete operating system (e.g., Windows or Linux) and applications, just like a real computer. Because they are isolated, a crash or a security issue in one VM does not affect the other VMs running on the same physical host.

  Virtualization is a foundational technology for cloud computing because it allows cloud providers to efficiently partition their massive physical servers into smaller, sellable units for thousands of different customers.