A virtual machine is a software emulation of a physical computer that runs an operating system and applications in an isolated environment. Virtual machines allow multiple OS instances to run on the same hardware using a hypervisor. Each VM receives virtualized CPU, memory, storage, and network resources. VMs make it possible to consolidate workloads, improve isolation, and simplify testing environments. Cloud providers rely heavily on virtual machines to provision compute resources on demand.
how it works
A hypervisor sits between the hardware and the virtual machines, allocating CPU time, RAM, and storage. When a VM boots, it loads its own operating system just as a physical machine would. VMs can be snapshotted, cloned, paused, or migrated across hosts. They isolate applications more strongly than containers but require more resources. Virtual machines are used for running legacy workloads, isolating untrusted code, and creating reproducible development environments.