The relationship between KVM and QEMU

The relationship between QEMU and KVM:

Virtualization, which is now described, is generally referred to as virtualization technology based on CPU hardware support. KVM relies on this technology as well as Hyper-V and Xen. Without the support of CPU hardware virtualization, KVM is not working.
To be exact, KVM is a module of Linux. You can use Modprobe to load the KVM module. After the module is loaded, you can further create the virtual machine from another tool. But only the KVM module is not enough, because the user cannot directly control the kernel module to do things: there must be a user-space tool. This user-space tool, the developer chooses the already formed open source virtualization software QEMU. It says QEMU is also a virtualization software. It is characterized by a virtual different CPU. For example, a power CPU can be virtualized on a x86 CPU, and it can be used to compile programs that can run on power. KVM uses a subset of QEMU and is transformed into a user-space tool that can control KVM. So you'll see that the official KVM download has two major three files, namely the KVM module, the Qemu tool, and the collection. That is, you can upgrade only the KVM module, or you can upgrade only the Qemu tool. This is the relationship between KVM and QEMU.