What capability allows a computer to simulate running multiple other computers simultaneously?

Virtualization is the capability that enables a computer to simulate multiple other computers simultaneously by running virtual machines (VMs). Each virtual machine operates as if it is a separate physical computer, complete with its own operating system and applications, while sharing the underlying hardware resources of the host machine. This technology allows for efficient resource utilization, as multiple VMs can run concurrently on a single physical server, reducing hardware costs and improving deployment speed.

In the context of virtualization, different types of software, such as hypervisors, manage various VMs and allocate resources effectively among them. This technology is widely used in server environments, cloud computing, and for testing purposes where isolated environments are beneficial.

Threading and multithreading pertain more to how a program can run multiple threads (smaller units of a process) concurrently within a single instance but do not enable the simulation of distinct computers. Multi-core processing refers to having multiple processing cores within a single CPU, which enhances performance but does not inherently allow for the simulation of separate computers as virtualization does.