A key benefit of virtualization is the ability to run multiple operating systems on a single physical system and share the underlying hardware resources known as partitioning.
- Hardware-level virtualization,
- Operating systemlevel virtualization,
- and high-level language virtual machines.
For Unix/RISC and industry-standard x86 systems, the two approaches typically used with software-based partitioning are hosted and hypervisor architectures .
A hosted approach provides partitioning services on top of a standard operating system and supports the broadest range of hardware configurations.
In contrast, a hypervisor architecture is the first layer of software installed on a clean x86-based system (hence it is often referred to as a “bare metal” approach). Since it has direct access to the hardware resources, a hypervisor is more efficient than hosted architectures, enabling greater scalability,robustness and performance.