Terrific account of file system history
PC technology website Ars Technica has a great history of file systems. The story begins with the very first minicomputer, the PDP 8 and its tape-based file sysyem. It moves on to the PC and its rudimentary floppy disk-based file system and then the flowering of Microsoft and Unix.
You can read the series of six or so pages – 6,500+ words – with illustrations at Ars Technica.