Glossary Updates12 new terms added to the glossaries · October 2, 2026, 22:44 CEST
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Glossary · Automation software engineering and architecture

Virtual machine (VM)

Also known as: VM

German: Virtuelle Maschine (VM)

In computing, a virtual machine (VM) is a software emulation of a complete computer, with its own virtual processor, memory, storage and network interfaces, on which an operating system and applications run isolated from other VMs on the same physical host.

  • Software engineering

In one sentence

A virtual machine (VM) emulates a complete computer in software, running its own OS and applications isolated on a shared host.

Example

The plant runs its SCADA server, historian and engineering workstation as virtual machines on one redundant server cluster.

How it applies

  • Engineering: VMs consolidate servers, simplify backup and allow snapshots before changes. Some vendors offer virtual PLCs that run control software in VMs on real-time hypervisors.
  • Security: Separating functions into VMs supports zoning under IEC 62443, but the hypervisor becomes a critical component whose compromise affects all VMs.
  • Documentation: State which virtualization platforms and versions are supported, the resources a VM needs and any restrictions, such as timing guarantees not holding when resources are overcommitted.

Virtual machine vs. container

A VM includes a full guest operating system. A Container shares the host's kernel and packages only the application and its dependencies, so it is lighter but less isolated. In programming languages, virtual machine also denotes a runtime such as the Java VM.

By knowledge.aitechdoc.world · Published September 26, 2026 · Last reviewed

Source: AI TechDoc Knowledge editorial definition, based on virtualization practice

Definitions follow the cited standards and specifications. Where a source is a copyrighted publication, such as an ISO, IEC or EN standard, the definition is a close paraphrase, not a verbatim quotation, so as not to infringe copyright. We recommend reading the original publication. The sections “How it applies” are editorial commentary by AI TechDoc Knowledge and are not part of any standard.

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