QEMU [3] is an emulator used to run programs for one machine on another.
N64 [4] is the Nintendo 64 games console.
SGI Indy [5] was a desktop SGI workstation from 1993.
[1] https://en.wikipedia.org/wiki/IRIX
[2] https://en.wikipedia.org/wiki/Silicon_Graphics
UNIX: Actually Unix. Not an acronym. https://en.m.wikipedia.org/wiki/Unix
Sorta.
"In 1970, the group coined the name Unics for Uniplexed Information and Computing Service (pronounced "eunuchs"), as a pun on Multics, which stood for Multiplexed Information and Computer Services."
More specifically one processor architecture to another. E.g. running on your desktop (usually an x86 based architecture) a Linux Operating System designed and compiled for a Raspberry Pi (ARM based architecture) and it's incompatible architecture. In this case they're running software designed for the same processor that the Nintendo 64 was targeting which so happens to also have ran a Unix OS known as IRIX.
edit: oh, says it right there in the Wiki