Fenestra '98

Fenestra '98 was a computer operating system developed by Macrosoft and was used by certain terminals aboard the Enclave Oil Rig.

Background
It received negative critical reception for its excessive and long loading times, especially for loading the system.

Appearances
Fenestra '98 is mentioned only in Fallout 2.

Behind the scenes
Fenestra means "window" in Latin, making it a reference to Microsoft Windows, in particular, Windows 98.