Files, and the ordering of folder hierarchy from left to right, was developed by Unix in the 1970s. Domain names (DNS) were developed in 1985 to locate things

Files, and the ordering of folder hierarchy from left to right, was developed by Unix in the 1970s. Domain names (DNS) were developed in 1985 to locate things on the Internet, entirely separately, with the opposite hierarchical ordering. The convention of locating files on a system identified by a domain name wasn't developed until 1992 and standardized in 1994 as a URL. As a result, we have two hierarchical orderings for two separate things, because they were merged later on.