What this system is, when and why it was created, and by whom.
The history, goals, and real-world use cases behind FreeDOS, the open-source, actively-maintained continuation of the MS-DOS-compatible operating system line.
How FreeBSD grew from the 386BSD Patchkit, survived the Net/2 transition, and built the release, ports, and governance model used today.
Trace Linux from Torvalds' 1991 announcement and early licensing through distributions, maintainership, Git and today's release process.
How Apple's 1996 acquisition of NeXT, and Steve Jobs' return, turned NeXTSTEP into the Unix foundation underneath every Mac sold today.
How MAME, DOSBox, libretro, reverse engineering, hardware research, and archival practice turned emulation into a preservation discipline.
How Microsoft's 1975 founding led, eighteen years later, to hiring a DEC operating-system veteran to build Windows NT from scratch.