the.com/virtual machine
A computer pretending to be a computer, inside another computer.
means A software program that emulates a complete computer system, running its own operating system and applications as if it were separate physical hardware.
from 'Virtual' traces back to Latin 'virtus' (strength, virtue, capability) — through medieval optics and physics it came to mean 'possessing the essential qualities of something without the actual form,' as in a 'virtual image' in a mirror. Computing borrowed exactly this sense in the mid-20th century: IBM researchers in the 1960s building time-sharing systems needed a word for something that behaved like a real machine but wasn't one physically — so 'virtual' memory and 'virtual' machines were born, giving each user the convincing illusion of their own dedicated computer, sharing one real set of hardware underneath.
- origin
- IBM built the first in 1972 for timesharing
- magic trick
- hardware is faked so software never notices
- cost of lying
- slower than real hardware, always
- modern cousin
- containers share one kernel instead of faking many