Mac OS 9 was my first real introduction to the Macintosh OS; it was installed on the iMac DVSE I bought in late 1999. Before that the only experience of Mac OS that I'd had was dabbling on some of the Macs that the molecular biologists used at work.
Although it was somewhat crash-prone (depending on which extensions were installed), I definitely preferred Mac OS 9 to Windows 95 which was on the last PC I owned.
