@trechnex i think it's actually probably a hangover from when "computer system" was the size of one or multiple fridges which would be delivered on a lorry and installed by a team of technicians from the computer company, who would also install the software into the system. the complete system was the hardware and the software packages, provided by DEC or IBM or ICL or whoever, so there wasn't much separation between OS and other software, it was just 'the configured system'