It’s interesting that this classification isn’t new. In fact it was classified by Gerald J. Popek back in 1974 in the article “Formal Requirements for Virtualizable Third Generation Architectures”

So to answer the question:

A hypervisor is a hardware virtualization technique which allows multiple guest operating systems to run on a single host system hardware at the same time. Each guess operating system share the hardware its host. Hardware such as processor, memory as if it is its own.

Type 1 Hypervisors are known as bare-metal. These run directly on the host hardware and have full control of the hardware resources while managing guest operating systems.

Type 2 Hypervisors are hosted and run within a host operating systems environment to provide virtualization resources

Examples of Type 1 Hypervisors include: VMware ESXi, Citrix XenServer, Microsoft Hyper-V, KVM (Kernel-based Virtual Machine) on Linux.

Examples of Type 2 Hypervisors include: VMware Workstation / Player / Fusion, Sun VirtualBox, Parallels


I hope you enjoyed this #techshort and thanks for visiting – jermal