Technically, the original Macintosh filesystem supported folders as "an illusion maintained by the system software"[1] in spite of its flat directory structure.

Technically, the original Macintosh filesystem supported folders as "an illusion maintained by the system software"[1] in spite of its flat directory structure. [1] https://developer.apple.com/library/archive/documentation/mac/Files/Files-85.html https://developer.apple.com/library/archive/documentation/ma...