"QEMU lets you emulate a machine--in other words, you can run a virtual computer on top of your real computer. This makes it perfect for trying the latest release of a distribution, running older operating systems, or just testing.
"Getting QEMU depends on your operating system--if you're on Debian, for instance, you can type apt-get install qemu. However, in order to get the latest version, as well as to avoid a bug in the version in the Debian repositories, you might want to download QEMU from upstream. If you're using an x86 machine, such as the AMD Athlon, Intel Pentium, or Intel Core, in 32-bit mode, then you can safely choose 'Binary distribution for linux-i386.' Simply extract the contents, as root, to /, making sure to maintain the directory structure..."
