FAT (file allocation table)

A file system based on a file allocation table (FAT) maintained by some operating systems, including Windows, to keep track of the status of various segments of disk space used for file storage.


A derivative of the file allocation table file system. FAT32 supports smaller cluster sizes than FAT in the same given disk space, which results in more efficient space allocation on FAT32 drives. See also FAT; NTFS file system.


A collection of information that has been given a name and is stored on a disk. This information can be a document or an application.


The name of a file. MS-DOS supports the 8.3 naming convention of up to eight characters followed by a period and a three-character extension. Windows supports the FAT and NTFS file systems with filenames up to 255 characters. Since MS-DOS cannot recognize long filenames, Windows automatically translates long names of files and folders to 8.3 names for MS-DOS users. See also long name; name mapping; short name.

filename extension

The characters that follow the last period in a filename. Filename extensions are often used to identify the type of file and the application used to create the file.

file system

In an operating system, the overall structure in which files are named, stored, and organized. NTFS, FAT, and FAT32 are types of file systems.

file viewer

A file viewer is a plugin or module that displays data stored in file and provides thumbnails for panel. Common type of file viewer is picture viewer or text viewer.

floppy disk

A disk that can be inserted in and removed from a disk drive. Floppies are most commonly available in a 3.5 or 5.25 inch format.


A grouping of files or other folders, graphically represented by a folder icon, in the Windows environment. A folder is analogous to a PC's file system directory, and many folders are, in fact, directories. A folder may contain other folders as well as file objects. See also directory.

free space

Available space that is used to create logical drives within an extended partition.

full path

A full path is a path that fully specifies the file or directory. It does not matter where you use such path (on your computer), it always address one file or directory. See also relative path, local path, UNC, and path.