Path (computing)

A path, the general form of the name of a file or directory, specifies a unique location in a file system. A path points to a file system location by following the directory tree hierarchy expressed in a string of characters in which path components, separated by a delimiting character, represent each directory. The delimiting character is most commonly the slash ("/"), the backslash character ("\"), or colon (":"), though some operating systems may use a different delimiter. Paths are used extensively in computer science to represent the directory/file relationships common in modern operating systems, and are essential in the construction of Uniform Resource Locators (URLs). Resources can be represented by either absolute or relative paths.

History

Around 1970, Unix introduced the forward slash character ("/") as its directory separator. In 1981, when the original version of Microsoft DOS (MS-DOS 1.0) was released, Microsoft DOS did not support directories. A major portion of the utilities packaged with DOS came from IBM. The command line prompts of these IBM-written utilities made use of the forward slash character as a "switch" which is still existent today (as in dir /w tells the dir command to run with the wide list format option). However, on Unix the dash ("-") character is used for switches. When directory support was introduced in MS-DOS 2.0, IBM desired to keep compatibility with the original DOS utilities, and a host of other programs that had been written to use the forward slash as a switching character. Since the forward slash character already served as a switching utility, Microsoft chose the back slash character ("\") which character-wise looks very similar to the forward slash character ("/") to indicate directory separation.