Brief History: 

Before we introduce and define Virtualization, we need to understand the origin of Virtualization. Before the rise of Virtualization, the Applications, and software run on a physical computer inside a Datacenter. Large Infrastructure running inside Datacenter introduced numerous challenges. The cost is a major factor that includes but not limited to Power, cabling, rack space, cooling, square foot area inside Datacenter for physical hardware, IT staff for management, etc. Also, in the Datacenter model, there is one to one mapping between the software and the computer. As a result, most of the systems are underutilized. Lastly setting up the infrastructure inside a Datacenter is a time-consuming process.