Describe the key differences between a Type 1 (bare-metal) and Type 2 (hosted) hypervisor and provide a use-case example for each.

The key difference between a Type 1 (bare-metal) and a Type 2 (hosted) hypervisor lies in their architecture and how they interact with the hardware. A Type 1 hypervisor, also known as a bare-metal hypervisor, runs directly on the hardware. This means there is no underlying operating system between the hypervisor and the physical hardware. Examples of Type 1 hypervisors include VMware ESXi and Microsoft Hyper-V Server. Because it runs directly on the hardware, a Type 1 hypervisor has direct access to system resources, resulting in better performance and efficiency. It also tends to be more secure because it reduces the attack surface by eliminating the need for a host operating system. A use-case example for a Type 1 hypervisor is in enterprise data centers where high performance and security are critical. For instance, a company might use VMware ESXi to host multiple virtual servers (web servers, database servers, application servers) on a single physical server, optimizing resource utilization and reducing hardware costs. On the other hand, a Type 2 hypervisor, also known as a hosted hypervisor, runs on top of an existing operating system. This means the hypervisor relies on the host operating system for access to hardware resources. Examples of Type 2 hypervisors include VMware Workstation and Oracle VirtualBox. Because it relies on the host OS, a Type 2 hypervisor typically has lower performance compared to a Type 1 hypervisor. The host OS consumes some resources, and the hypervisor must go through the host OS to access hardware. Also, security depends on the security of the host OS. A use-case example for a Type 2 hypervisor is a software developer who needs to test applications on different operating systems. The developer can use VirtualBox on their Windows or macOS machine to run virtual machines with Linux or other operating systems, allowing them to test their software in different environments without needing multiple physical computers.