Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Partial virtualization, in computer science, is a virtualization technique used to implement a certain kind of virtual machine environment: one that provides a partial simulation of the underlying hardware. Most but not all of the hardware features are simulated, yielding virtual machines in which some but not all software can be run without modification. Usually, this means that entire operating systems cannot run in the virtual machine which would be the sign of full virtualization but that many applications can run.