ouroborOS is the operating system used by Mars on his desktop computer. It's name is a reference to Ouroboros, the ancient symbols of a snake eating it's own tail.[1] This is reinforced visually be it's logo, seen on page 112, while the PC is booting, we see what looks like two minimalist snakes eating each other's tails.
It's UI appears similar to that of Microsoft:Windows, with a taskbar at the bottom of the screen, a start menu on the left and three buttons on the right side of each windows' title bar. If a window needs user's attention it's icon turns orange.