Directory (computing)

On many computers, directories are known as folders or drawers,[1] analogous to a workbench or the traditional office filing cabinet.

The name derives from books like a telephone directory that lists the phone numbers of all the people living in a certain area.

[4] The name folder, presenting an analogy to the file folder used in offices, and used in a hierarchical file system design for the Electronic Recording Machine, Accounting (ERMA) Mark 1 published in 1958[5] as well as by Xerox Star,[6] is used in almost all modern operating systems' desktop environments.

There is a difference between a directory, which is a file system concept, and the graphical user interface metaphor that is used to represent it (a folder).

For example, Microsoft Windows uses the concept of special folders to help present the contents of the computer to the user in a fairly consistent way that frees the user from having to deal with absolute directory paths, which can vary between versions of Windows, and between individual installations.

[citation needed] The term directory refers to the way a structured list of document files and folders are stored on the computer.

Operating systems that support hierarchical filesystems (practically all modern ones) implement a form of caching to RAM of recent path lookups.

Screenshot of a Microsoft Windows command prompt window showing a directory listing.
Diagram of a hierarchical directory tree. The root directory is here called "MFD", for Master File Directory. Usually a file can only be in one directory at a time, but here File 2 is hard linked so it appears in two directories.
Sample folder icon (from KDE ).