Understanding Virtualization

Virtualization is a big topic, but very roughly speaking there are three main levels of virtualization:

• OS virtualization with a type 1 hypervisor
• Virtual machine that run on an existing hardware/OS, e.g. VMWare
• High-level virtual machines, e.g. JVM

I would recommend this book: Virtual Machines, by J. E. Smith and R. Nair.

It covers pretty much all virtual execution environments: process virtualization, high level virtual machines, system virtual machines, multiprocessor virtualization, etc.

Note that depending on the level which you are interested in, it gets pretty much related to system administration / hardware, so you might also ask the question on serverfault.com.