A subdivision of the hard disk for organizing data. Folders contain files as well as other folders (subfolders), and they expand to accommodate content because they are not a fixed, physical entity. Folders create the illusion of compartments, but actually exist as electronic tables of contents. See file.|
Folders are created by the operating system and applications when they are installed, and users create them for their own purposes. For example, right click on the desktop and select "New Folder." The data created with the application may or may not be stored in separate folders; for example, the Documents and My Documents folders in Windows are often used to store a variety of different types of data (spreadsheets, text documents, etc.).
Folders and Directories
The folder metaphor was introduced on the Xerox Star in 1981; later popularized on the Mac and Windows. In the earlier Unix and DOS environments, the same organization structure was called a "directory," and subfolders were called "subdirectories."
Since the Mac actually became a Unix computer, and the Unix/Linux worlds thrive along with Windows, the terms "folder" and "directory" are used synonymously. In fact, it is not uncommon for people to intersperse the two terms in the same sentence. See files vs. folders, file and Win Folder organization.
Folders in all graphical environments are pictured as paper file folders, the type that fit in a file cabinet. This excerpt from a Mac desktop shows two files (top) and two folders (bottom).