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A bit of hair splitting, but technically it's an emulator, not a VM, since it's just simulating the CPU using javascript in your browser.

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It is a base64 encoded highly optimized x86 assembly in DOSBox emulator inside a Javascript VM Chrome browser inside my Windows 10 Sandbox Nested Hyper-V VM inside VMware Workstation inside my Windows 10 machine.

It’s turtles all the way down.

Yeah, and then CPU which translates x86 code into uOPs.

There's always a relevant xkcd: https://xkcd.com/676/

Emulators are VMs too.

Well, depends a bit on what definitions you use.

For example there's VM in the sense of JVM. But there's also in VM in the sense of Xen (VM) vs Docker (not a VM).

And probably a few more slightly different usages.

Those are both VMs in the same sense. A VM creates an abstract, indirect implementation of a computing system. Sometimes that's with a lot of hardware offload as in Xen or picojava. Sometimes that's with a JIT as in HotSpot, orginal VMWare, or Transmeta. Sometimes that's just with an interpreter like the original JVM or Dosbox.

They're all virtual machines whether they're running code originally meant for execution on hardware or not.

That's a pretty wide definition. One that also encompasses any 'bare metal' OS, because they use microcode these days.

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