There are two bits of software which make the Satiator run: the firmware and the menu.

The firmware is flashed to the Satiator itself. The firmware is where the magic happens - hooking itself into the Saturn's CD block, emulating discs, et cetera. New firmware is loaded by putting a satiator.fw on your SD card; see the instructions below for more detail.

The menu is stored on the SD card, in the file menu.bin. The menu is the code that runs on the Saturn to list all your games and so forth.