What Is a Hypervisor?

A hypervisor is a software layer that allows virtualization by running multiple virtual machines (VMs) on top of a single physical server. It therefore creates and manages several VMs, each with its personal OS and resources, along with a physical server. Hypervisors ensure optimal resource utilization while enhancing scalability and reducing hardware dependency.

Hypervisor types:  

• Type 1 Hypervisor (Bare-metal) - The underlying host system is where the hypervisor operates directly. Other names for it include "Native Hypervisor" and "Bare Metal Hypervisor." No basic server operating system is necessary. Hardware resources are directly accessible to it. Suitable examples of such type include VMware ESXi and Microsoft Hyper-V.  
• Type 2 Hypervisor (Hosted) - They run along with the existence of some other operating system. Such hypervisors are commonly used for desktop virtualization with virtual desktop infrastructure and testing environments. Some examples include Oracle VirtualBox and VMware Workstation.

Hypervisors handle resource management such as CPU, memory, and storage, maintaining isolation between VMs. This consequently offers better security since the compromised VM cannot influence others easily.