While it's true that each operating system is different, and therefore there are various ways to use access methods for optimal information organization, when a user accesses their hard drive through File Explorer, for example, they may see a significant number of files that appear to be unknown.
In this sense, these are the system files that essentially operate according to the user's needs and data usage within a given operating system, whether it's Windows, Mac, or Linux . Therefore, they all contain a large number of folders and files of different types.
So, to learn more about how system files are defined and what they're actually used for, we invite you to continue reading this post. Here, you'll also find a complete list of all the file extension types used by the system , along with the programs needed to access them.
What are system files and what are they actually used for?
Essentially, system files are defined as the methods and data structures that an operating system uses to keep track of the records on a disk or partition ; in other words, they are how files are organized on the hard drive. Thus, they refer to a group of crucial file formats that are essential for the proper functioning of a computer's operating system.
Therefore, if any of these files are missing, modified, or damaged, the operating system will immediately malfunction or fail to boot completely . Consequently, if a user attempts to delete a system file, an error message will appear indicating that the file is being used by the OS . However, as a preventative measure, these files are kept hidden or invisible to users.
It's important to note that some types of system files include system libraries, device drivers, icons, and themes. These files are characterized by their incompatibility across different platforms ; each platform has its own native binary formats for a specific operating system (Windows, Mac, or Linux). For example, system files for macOS do not function as system files for Microsoft Windows or Linux.
Types of system file extensions and their associated programs to open them
Therefore, it's important to highlight that system files are essential for organizing a computer's files and all the information stored on it . This simplifies the administration and maintenance of the computer; system files are the way files are saved on storage devices, and each operating system has its own specific file system.
Therefore, given their great importance, it is valuable to know each and every type of file extension that currently exists in the system . For this reason , we will now list them along with their associated software for opening them on each operating system:
|
Extension types |
Associated with: |
Operating System |
| 2fs | Puppy Linux Save State File | Linux |
| 386 | Windows Virtual Device Driver | Microsoft Windows |
| 3fs | Puppy Linux Save State File | Linux |
| 73u | TI-73 Explorer Operating System File | Microsoft Windows and Mac OS |
| 8xu | TI-83 Plus Operating System File | Microsoft Windows |
| adm | Administrative Template File | Microsoft Windows |
| adml | Microsoft language-specific XML template file | Microsoft Windows |
| admx | Group Policy Administrative Template File | Microsoft Windows |
| aml | Microsoft Assistance Markup Language | Microsoft Windows |
| ani | Animated cursor | Microsoft Windows |
| ann | Help Annotations | Microsoft Windows |
| to | ARCHOS PCtablet Firmware File | Microsoft Windows |
| asec | Android Secure Application File | Microsoft Windows |
| atahd | ATA Hard Drive Flag File | Microsoft Windows |
| automaticdestinations-ms | Windows Jump List File | Microsoft Windows |
| bashrc | Bash Non-Interactive Login Shell File | Microsoft Windows, Mac OS and Linux |
| bash_history | Bash History File | Mac OS and Linux |
| bash_profile | Bash Interactive Login Shell File | Mac OS and Linux |
| BCD | Windows Boot Configuration Data File | Microsoft Windows |
| bk2 | Windows Indexing Service Data File | Microsoft Windows |
| bff | Microsoft Windows Vista and Windows 7 registry file | Microsoft Windows |
| boom | Mac OS X Bill of Materials File | Mac OS |
| bud | Binary Printer Description File | Microsoft Windows and Mac OS |
| c32 | Syslinux COM32 Module | Linux |
| cab | Windows Cabinet File | Microsoft Windows |
| cat | Microsoft Security Catalog file | Microsoft Windows |
| cdmp | WCS Device Model Profile | Microsoft Windows |
| cgz | Linux Drivers Archive | Linux |
| chs | Windows Chinese Noise-Word List File | Microsoft Windows |
| cns | Windows 2000 Client Connection Manager Export file | Microsoft Windows |
| cnt | Help Contents File | Microsoft Windows |
| configprofile | Apple Configuration Profile | Mac OS |
| Cpl | Windows Control Panel Item | Microsoft Windows |
| cpq | Compaq OEM Disc Configuration File | Microsoft Windows |
| crash | Mac OS X Crash Log File | Mac OS |
| ass | Windows Cursor | Microsoft Windows |
| desklink | Desktop Shortcut | Microsoft Windows |
| deskthemepack | Windows 8 Desktop Theme Pack File | Microsoft Windows |
| giant | Windows Device Driver File | Microsoft Windows |
| dfu | iOS DFU File | Mac OS |
| diagcab | Troubleshooting Pack Cabinet File | Microsoft Windows |
| diagcfg | Troubleshooting Pack Configuration File | Microsoft Windows |
| diagpkg | Troubleshooting Pack File | Microsoft Windows |
| dimax | DiMAX Firmware Image File | Microsoft Windows |
| your | Active Directory Information Tree File | Microsoft Windows |
| dll | Dynamic Link Library | Microsoft Windows |
| dmp | Windows Memory Dump | Microsoft Windows |
| drpm | Delta RPM File | Microsoft Windows |
| drv | Device Drivers | Microsoft Windows |
| DYC | Xerox Printer Driver Configuration File | Microsoft Windows |
| ibid | Windows EBD System File | Microsoft Windows |
| edj | Enlightenment Theme File | Microsoft Windows |
| efi | Extensible Firmware Interface File | Microsoft Windows, Mac OS and Linux |
| efires | EFI Image File | Mac OS |
| emerald | Emerald Theme | Linux |
| etl | Microsoft Event Trace Log File | Microsoft Windows |
| Possibly | Windows Event Viewer Log File | Microsoft Windows |
| eventx | Windows 7 Event Log File | Microsoft Windows |
| fFA | Find Fast Status File | Microsoft Windows |
| ffl | Find Fast Document List | Microsoft Windows |
| ffo | Find Fast Document Properties Cache | Microsoft Windows |
| fpbf | Mac OS X Burn Folder | Mac OS |
| ftg | Full Text Group | Microsoft Windows |
| gmmp | WCS Gamut Map Model Profile | Microsoft Windows |
| grl | Windows Update Status File | Microsoft Windows |
| group | Windows Contacts Group File | Microsoft Windows |
| h1s | Windows Assistance Platform Help File | Microsoft Windows |
| hdmp | Windows Heap Dump | Microsoft Windows |
| help | Mac OS X Help Book | Mac OS |
| hhhh | HTML Help Table of Contents | Microsoft Windows |
| hhk | HTML Help Index | Microsoft Windows |
| hiv | Windows Registry Hive File | Microsoft Windows |
| hlp | Windows Help File | Microsoft Windows |
| hpd | Help Project File | Microsoft Windows and Mac OS |
| hsh | Windows Catalog Search Index File | Microsoft Windows |
| htt | Hypertext Template File | Microsoft Windows |
| icl | Windows Icon Library File | Microsoft Windows |
| ICNS | Mac OS X Icon Resource File | Mac OS |
| ico | Icon File | Microsoft Windows |
| iconpackage | IconPackager Theme File | Microsoft Windows |
| ifw | INTUS Firmware File | Microsoft Windows |
| ime | Windows Input Method Editor File | Microsoft Windows |
| img3 | iPhone IMG3 File | Mac OS |
| img3 | iPhone IMG3 File | Mac OS |
| inf_loc | Windows Driver Information Cache File | Microsoft Windows |
| internetconnect | Apple Internet Connect Document | Mac OS |
| ion | File Description File | Microsoft Windows and Linux |
| ioplist | Mac OS X IOPLIST File | Mac OS |
| ipod | Rockbox Firmware File | Mac OS |
| iptheme | IconPackager Raw Theme File | Microsoft Windows |
| itemdata-ms | Windows 8 Start Screen Item Data File | Microsoft Windows |
| ius | InfoTMIC Firmware Update File | Microsoft Windows |
| job | Windows Task Scheduler Job File | Microsoft Windows |
| jpn | Windows Japanese Noise-Word List File | Microsoft Windows |
| kbd | Keyboard Layout Script | Microsoft Windows, Mac OS and Linux |
| kext | Mac OS X Kernel Extension | Mac OS |
| ko | Linux Kernel Module File | Linux |
| Kor | Windows Korean Noise-Words List File | Microsoft Windows |
| library-ms | Windows Library Description File | Microsoft Windows |
| lnk | Windows File Shortcut | Microsoft Windows |
| lockfile | Mac OS X PLIST Lock File | Mac OS |
| log1 | Windows Registry Hive Log File | Microsoft Windows |
| log2 | Windows Registry Hive Log 2 File | Microsoft Windows |
| lpd | Lookout Protocol Driver File | Microsoft Windows, Mac OS and Linux |
| manifest | Windows Application Manifest File | Microsoft Windows |
| mapimail | Send to Mail Recipient | Microsoft Windows |
| mdmp | Windows Minidump | Microsoft Windows |
| metadata_never_index | Spotlight Never Index File | Microsoft Windows |
| mi4 | Audio Player Firmware File | Microsoft Windows, Mac OS and Linux |
| mlc | Microsoft Language Interface Pack | Microsoft Windows |
| mobileconfig | Apple Mobile Configuration File | Mac OS |
| msc | Microsoft Management Console Snap-in Control File | Microsoft Windows |
| msp | Windows Installer Patch | Microsoft Windows |
| msstyle | Windows XP Unsigned Style | Microsoft Windows |
| msstyles | Windows XP Style | Microsoft Windows |
| mtz | MIUI-Theme | Microsoft Windows |
| mui | Multilingual User Interface File | Microsoft Windows |
| mui_cccd5ae0 | Hidden User Library | Microsoft Windows |
| mum | Windows Vista Update Package | Microsoft Windows |
| mydocs | Send to My Documents | Microsoft Windows |
| nbh | ROM Update Utility Image File | Microsoft Windows |
| networkconnect | Apple Network Connect Document | Mac OS |
| nls | Microsoft National Language Support File | Microsoft Windows |
| nt | Windows NT Startup File | Microsoft Windows |
| ntfs | NTFS Partition File | Microsoft Windows |
| Osax | FindFile OSAX mac file type | Microsoft Windows |
| panic | Kernel Panic File | Mac OS and Linux |
| pdr | Windows Port Driver | Microsoft Windows |
| pf | Windows prefetch file | Microsoft Windows |
| pfx | PKCS #12 Certificate File | Microsoft Windows and Mac OS |
| pk2 | Silkroad Online Game Data File | Microsoft Windows |
| Pop | Precompiled INF File | Microsoft Windows |
| ppd | PostScript Printer Description File | Microsoft Windows |
| prefpane | Mac OS X System Preference Pane | Mac OS |
| printerexport | Windows Printer Migration File | Microsoft Windows |
| profile | Bash Shell Profile | Mac OS and Linux |
| provisionprofile | Apple Provision Profile | Mac OS |
| pwl | Windows Password List | Microsoft Windows |
| qky | Quirky Kernel | Microsoft Windows |
| rco | PlayStation Portable Resource File | Microsoft Windows |
| reg | Registry File | Microsoft Windows |
| regtrans-ms | Registry Transaction Log File | Microsoft Windows |
| rfw | Rockchip Firmware File | Microsoft Windows |
| rmt | Router Firmware File | Microsoft Windows and Mac OS |
| haha | Windows Installer temporary file file | Microsoft Windows |
| rtp | Microsoft software update file | Microsoft Windows |
| savedsearch | Spotlight Saved Search | Microsoft Windows |
| saver | Mac OS X Screen Saver | Mac OS |
| scap | EFI Firmware File | Microsoft Windows |
| scf | Windows Explorer Command | Microsoft Windows |
| diagrams | GConf Schema Definition File | Linux |
| scr | Windows Screensaver | Microsoft Windows |
| searchconnector-ms | Windows Search Connector File | Microsoft Windows |
| sfcache | ReadyBoost Cache File | Linux |
| shhd | Windows Print Job Shadow File | Microsoft Windows |
| So0 | Unix Shared Library File | Linux |
| sp3 | Microsoft Windows XP with Service Pack 3 installation file | Microsoft Windows |
| spl | Windows Print Spool File | Microsoft Windows |
| sqm | Service Quality Monitoring File | Microsoft Windows |
| sys | Windows System File | Microsoft Windows |
| tdz | Drobo Firmware File | Microsoft Windows and Mac OS |
| tha | Windows Thai Noise-Words List File | Microsoft Windows |
| theme | Microsoft Plus! Desktop Theme | Microsoft Windows |
| trx_dll | Windows Startup File | Microsoft Windows |
| uce | Windows UCE System File | Microsoft Windows |
| vga | VGA Display Driver | Microsoft Windows |
| vgd | Generic CADD VGA Driver | Microsoft Windows |
| vxd | Virtual Device Driver | Microsoft Windows |
| vx_ | Compressed Virtual Device Driver File | Microsoft Windows |
| wdgt | Dashboard widgets | Microsoft Windows |
| webpnp | Web Point and Print File | Microsoft Windows |
| who | Windows Error Report | Microsoft Windows |
| according to | S60 Web Runtime Widget Package | Microsoft Windows |
| xp | WindowBlinds temporary file | Microsoft Windows |
| xrm-ms | Microsoft Security Certificate | Microsoft Windows |
| zoneidentifier | Windows Zone Identifier File | Microsoft Windows |
