Virtualization may refer to:

Concept

Virtualization is the creation of a virtual (rather than actual) version of something, such as an operating system, a server, a storage device or network resources.

Virtualization can be viewed as part of an overall trend in enterprise IT that includes autonomic computing, a scenario in which the IT environment will be able to manage itself based on perceived activity, and utility computing, in which computer processing power is seen as a utility that clients can pay for only as needed. The usual goal of virtualization is to centralize administrative tasks while improving scalability and work loads.

Hardware

• Hardware virtualization, execution of software in an environment separated from the underlying hardware resources
  • Hardware-assisted virtualization, where some support for virtualization is built into the underlying hardware
  • Full virtualization, sufficiently complete simulation of the underlying hardware to allow software, typically a guest operating system, to run unmodified
  • Partial virtualization, where some but not all of the target environment is simulated. Some guests may need modifications to run, see paravirtualization
  • Paravirtualization, virtualization environments that require modifications to guest operating systems in exchange for higher efficiency

Memory

• Virtual memory, giving an application program the impression that it has contiguous working memory, isolating it from the underlying physical memory implementation
• Memory virtualization, aggregating RAM resources from networked systems into a single memory pool

Storage

• Storage virtualization, the process of completely abstracting logical storage from physical storage

Software

• Operating system-level virtualization, hosting of multiple virtualized environments within a single OS instance
  • Application virtualization, the hosting of individual applications in an environment separated from the underlying OS
• Virtual machine (VM), a software (possibly hardware-assisted) implementation of a computer that executes programs like a real computer

Mobile

• Mobile virtualization, using virtualization technology for mobile phones and other types of connected wireless devices

Data

• Data virtualization, the presentation of data as an abstract layer, independent of underlying database systems, structures and storage
• Database virtualization, the decoupling of the database layer, which lies between the storage and application layers within the application stack

Desktop

• Desktop virtualization, the remote display, hosting or manipulation of a graphical computer environment (desktop)

Network

• Network virtualization, creation of a virtualized network addressing space within or across network subnets