it is just abstraction over host operating system, you remember there is concept of virtual memory, memory which physical don’t exist but to make things simpler we create virtual memory, hypervisor is also like the same we can say!
hypervisor is nothing but a piece of software which makes easy to create and monitor different different virtual machines
remeber playing with this bad boy ?
wasting days trying to boot macos ?
there are different different types of hypervisors: