Most old BIOSes on PCs and compatibles provided means to enter hard drive geometries (cylinder/head/sector as well as more esoteric things like write precomp) when configuring the machine.
Some (AMI for sure, also Phoenix? Others?) had a table of geometries for 40 or so drives, plus the ability to enter custom values. (Over the years larger drives, LBA, etc. would render this less relevant)
Anyway, my question is: where did these tables of hardcoded geometries originate from? Was there a list that all BIOS vendors used? Were they ever useful? In all the times in the late 80s/early 90s I never had a drive that mapped to an already-defined geometry.