So it's no secret that some parts of the army in the USA and my country (UK) sometimes use legacy software like DOS for niche roles as they're robust including older versions of Windows.
But.. where does Linux fit in this? It's a kernel OS that's used in top of the line supercomputers, workstations, medical equipment and weather stations.
I imagine some aspects of this would be military secrets but how do they use it? I know that Linux was used for certain space projects with NASA but I'm talking about army applications.
TLDR : Does the penguin OS power shooty shooty machines and tanks
There are many reasons Microsoft software is only "good" (and I'm using that word loosely) in business and home settings. Can you imagine a rocket taking off and windows suddenly "rebooting to complete updates" (or whatever it is that it says along those lines)?
Correct, missiles use something like RTEMS, which is named because it was used for missiles (no really, it originally stood for Real Time Executive for Missile Systems) and the operating demands for missiles have to be real-time given their unique edge cases.