Kernel-based Virtual Machine aka KVM
KVM (Kernel-based Virtual Machine) is an open source virtualization technology for Linux. It installs natively on all Linux distributions and turns underlying physical servers into hypervisors so that they can host multiple, isolated virtual machines (VMs). Kernel Virtual Machine consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko.
KVM requires a processor with hardware virtualization extensions, such as Intel VT or AMD-V. KVM supports hardware-assisted virtualization for a wide variety of guest operating systems including BSD, Solaris, Windows, Haiku, ReactOS, Plan 9, AROS, macOS, and more.
On a linux system you can check to see if KVM support is enabled with the cpu-checker utility
sudo apt install cpu-checker kvm-ok
The kvm-ok command will return something like the following if virtualization is enabled.
$ kvm-ok INFO: /dev/kvm exists KVM acceleration can be used
Software such as virtualbox requires virtualization enabled for purposes.