Editing File system (section)

{{Short description|Computer filing system}}
{{About|how a computer organizes and accesses computer files|library and office filing systems|Library classification}}
{{OS}}
In [[computing]], a '''file system''' or '''filesystem''' (often abbreviated to '''FS''' or '''fs''') governs [[computer file|file]] organization and access. A ''local'' file system is a capability of an [[operating system]] that services the applications running on the same [[computer]].<ref>{{cite web | title=5.10. Filesystems
|url=https://tldp.org/LDP/sag/html/filesystems.html
|publisher= The Linux Document Project
|access-date=December 11, 2021
|quote=A ''filesystem'' is the methods and data structures that an operating system uses to keep track of files on a disk or partition; that is, the way the files are organized on the disk.}}</ref><ref>{{citation|title=File System Implementation|url=http://pages.cs.wisc.edu/~remzi/OSTEP/file-implementation.pdf|publisher= Arpaci-Dusseau Books|year = 2014|first1 = Remzi H.|last1 =Arpaci-Dusseau|first2=Andrea C.|last2 = Arpaci-Dusseau}}</ref> A [[distributed file system]] is a [[Communication protocol|protocol]] that provides file access between [[computer network|networked]] computers.

A file system provides a [[computer data storage|data storage]] [[Service (systems architecture)|service]] that allows [[application software|application]]s to share [[mass storage]]. Without a file system, applications could access the storage in [[Software incompatibility|incompatible]] ways that lead to [[resource contention]], [[data corruption]] and [[data loss]].

There are many file system [[software design|designs]] and [[implementation]]s {{endash}} with various structure and features and various resulting characteristics such as speed, flexibility, security, size and more.

File systems have been developed for many types of [[Computer storage device|storage devices]], including [[hard disk drive]]s (HDDs), [[solid-state drive]]s (SSDs), [[magnetic tape]]s and [[optical disc]]s.<ref>{{cite web | title=Storage, IT Technology and Markets, Status and Evolution
|url=https://indico.cern.ch/event/713888/contributions/3122779/attachments/1719287/2774787/storage_tech_market_BPS_Sep2018_v6.pdf
|date=September 20, 2018
|quote=HDD still key storage for the foreseeable future, SSDs not cost effective for capacity}}</ref>

A portion of the computer [[random-access memory|main memory]] can be set up as a [[RAM disk]] that serves as a storage device for a file system. File systems such as [[tmpfs]] can store files in [[virtual memory]].

{{Anchor|VIRTUAL-FILE}}
A ''virtual'' file system provides access to files that are either computed on request, called ''virtual files'' (see [[procfs]] and [[sysfs]]), or are mapping into another, backing storage.