A file system (or filesystem) is an abstraction to store, retrieve and update a set of files. The term also identifies the data structures specified by some of those abstractions, which are designed to organize multiple files as a single stream of bytes, and the network protocols specified by some other of those abstractions, which are designed to allow files on a remote machine to be accessed. By extension, the term also identifies software or firmware components that implement the abstraction (i.e. that actually access the data source on behalf of other software or firmware that uses those components).
The file system manages access to the data and the metadata of the files, and manages the available space of the device(s) which contain it. Ensuring reliability is a major responsibility of a file system. A file system organizes data in an efficient manner, and may be tuned to the characteristics of the backing device.
Some file systems are used on data storage devices, to maintain the locations of the files on the device (which is seen as a stream of bytes). Others provide access to files residing on a server, by acting as clients for a network protocol (e.g. NFS, SMB, or 9P clients). Others provide access to data that is not stored on a persistent device, and/or may be computed on request (e.g. procfs). This is distinguished from a directory service and registry.
Famous quotes containing the words file and/or system:
“A common and natural result of an undue respect for law is, that you may see a file of soldiers, colonel, captain, corporal, privates, powder-monkeys, and all, marching in admirable order over hill and dale to the wars, against their wills, ay, against their common sense and consciences, which makes it very steep marching indeed, and produces a palpitation of the heart.”
—Henry David Thoreau (18171862)
“The twentieth-century artist who uses symbols is alienated because the system of symbols is a private one. After you have dealt with the symbols you are still private, you are still lonely, because you are not sure anyone will understand it except yourself. The ransom of privacy is that you are alone.”
—Louise Bourgeois (b. 1911)