System Files
The System Files category includes files related to Mac, Windows, and Linux operating systems. Some examples include system libraries, icons, themes, and device drivers. Files output by the system are also included in this category.
Common system file extensions include .DLL, .DRV, .SYS, and .CAB.
| Extension | File Type | Popularity |
|---|---|---|
| .LOCKFILE | Mac OS X PLIST Lock File | 4.7 |
| .AML | ACPI Machine Language File | 4.4 |
| .ADMX | Group Policy Administrative Template File | 4.4 |
| .REG | Registry File | 4.4 |
| .SERVICE | Systemd Service Unit File | 4.3 |
| .SHSH2 | iOS SHSH Blob | 4.3 |
| .VGA | VGA Display Driver | 4.3 |
| .CUR | Windows Cursor Image | 4.3 |
| .ITEMDATA-MS | Windows 8 Start Screen Item Data File | 4.3 |
| .RMT | Router Firmware File | 4.3 |
| .ANI | Windows Animated Cursor | 4.3 |
| .SEARCHCONNECTOR-MS | Windows Search Connector File | 4.3 |
| .CLB | COM+ Catalog File | 4.3 |
| .ICNS | macOS Icon Resource | 4.3 |
| .REGTRANS-MS | Registry Transaction Log File | 4.3 |
| .HTT | Hypertext Template | 4.3 |
| .WDGT | Dashboard Widget | 4.3 |
| .NT | Windows NT Startup File | 4.3 |
| .DLL | Dynamic Link Library | 4.2 |
| .DESKTHEMEPACK | Windows 8 Desktop Theme Pack File | 4.2 |
| .INF_LOC | Windows Driver Information Cache File | 4.2 |
| .ICONPACKAGE | IconPackager Theme File | 4.2 |
| .HVE | Windows Registry Hive File | 4.2 |
| .PK2 | Silkroad Online Game Data File | 4.2 |
| .DMP | Windows Memory Dump | 4.2 |
| .DVD | DOS Device Driver | 4.2 |
| .LNK | Windows Shortcut | 4.2 |
| .THEME | Microsoft Plus! Desktop Theme | 4.2 |
| .VX_ | Compressed Virtual Device Driver File | 4.2 |
| .QVM | Q Virtual Machine | 4.2 |
| .MDMP | Windows Minidump | 4.2 |
| .EBD | Windows EBD System File | 4.1 |
| .RC1 | Samsung Mobile Device Firmware File | 4.1 |
| .DESKLINK | Desktop Shortcut | 4.1 |
| .LIBRARY-MS | Windows Library Description File | 4.1 |
| .SYS | Windows System File | 4.1 |
| .ELF | Executable and Linkable Format File | 4.1 |
| .PCK | System Center Configuration Manager Package File | 4.1 |
| .HIV | Windows Registry Hive File | 4.1 |
| .73U | TI-73 Explorer Operating System File | 4.1 |
| .SFCACHE | ReadyBoost Cache File | 4.1 |
| .PROP | Android Build Properties File | 4.1 |
| .NFO | System Information File | 4.1 |
| .ASEC | Android Secure Application File | 4.1 |
| .ICO | Icon File | 4.1 |
| .FIRM | Boot9Strap 3DS Firmware File | 4.1 |
| .ION | File Description File | 4.1 |
| .FTF | FlashTool Firmware File | 4.1 |
| .MANIFEST | Windows Application Manifest File | 4.0 |
| .MUI | Multilingual User Interface File | 4.0 |
| .000 | Indexing Service Data File | 4.0 |
| .ETL | Microsoft Event Trace Log File | 4.0 |
| .ZONE.IDENTIFIER | Windows Zone Identifier File | 4.0 |
| .CI | Windows Content Indexer Catalog File | 4.0 |
| .BIN | Router Firmware File | 4.0 |
| .TIMER | Systemd Unit Configuration File | 4.0 |
| .FFX | Microsoft Find Fast Index | 4.0 |
| .CGZ | Linux Drivers Archive | 4.0 |
| .PWL | Windows Password List | 4.0 |
| .MSC | Microsoft Management Console Snap-in Control File | 4.0 |
| .MENU | macOS Menu Extra | 4.0 |
| .H1S | Windows Assistance Platform Help File | 4.0 |
| .EDJ | Enlightenment Theme File | 4.0 |
| .MOD | GRUB Module | 4.0 |
| .PREFPANE | Mac OS X System Preference Pane | 4.0 |
| .NLT | Windows Transliteration File | 4.0 |
| .MAPIMAIL | Send To Mail Recipient | 4.0 |
| .SCR | Windows Screensaver | 4.0 |
| .DAT | Windows Registry Hive File | 4.0 |
| .CM0013 | Samsung Smart TV Index File | 4.0 |
| .BASH_HISTORY | Bash History File | 4.0 |
| .ADM | Administrative Template File | 4.0 |
| .EFI | Extensible Firmware Interface File | 3.9 |
| .FX | ReadyBoot Trace File | 3.9 |
| .CAB | Windows Cabinet File | 3.9 |
| .WDF | Windows Driver Foundation File | 3.9 |
| .LFS | Samsung Phone params.lfs File | 3.9 |
| .MLC | Microsoft Language Interface Pack | 3.9 |
| .SDB | Custom Application Compatibility Database | 3.9 |
| .FOTA | Firmware Over-the-Air File | 3.9 |
| .MSSTYLES | Windows XP Style | 3.9 |
| .LOG1 | Windows Registry Hive Log File | 3.9 |
| .PNF | Precompiled INF File | 3.9 |
| .PIT | Samsung Phone Firmware File | 3.8 |
| .BASH_PROFILE | Bash Interactive Login Shell File | 3.8 |
| .C32 | Syslinux COM32 Module | 3.8 |
| .SYS | Motorola Driver File | 3.8 |
| .TRX_DLL | Windows Startup File | 3.8 |
| .MOBILECONFIG | Apple Mobile Configuration File | 3.8 |
| .DRV | Device Driver | 3.8 |
| .MTZ | MIUI Theme | 3.8 |
| .WEBPNP | Web Point and Print File | 3.8 |
| .HHK | HTML Help Index | 3.8 |
| .GROUP | Windows Contacts Group File | 3.8 |
| .SBN | Cisco IP Phone Firmware File | 3.8 |
| .0 | Shared Library Link File | 3.8 |
| .208 | ASUS Notebook BIOS 208 Update File | 3.8 |
| .BCD | Windows Boot Configuration Data File | 3.8 |
| .PDR | Windows Port Driver | 3.8 |
| .BASHRC | Bash Non-Interactive Login Shell File | 3.8 |
| .DIT | Active Directory Information Tree File | 3.8 |
| .PAT | DiskStation Manager Installation File | 3.8 |
| .MBR | Master Boot Record File | 3.8 |
| .INS | Internet Naming Service File | 3.8 |
| .MUI_CCCD5AE0 | Hid User Library | 3.8 |
| .3FS | Puppy Linux Save State File | 3.8 |
| .IMG3 | iPhone IMG3 File | 3.8 |
| .DEV | Windows Device Driver File | 3.8 |
| .IOPLIST | Mac OS X IOPLIST File | 3.8 |
| .MSP | Windows Installer Patch | 3.8 |
| .PLASMOID | Plasma Widget | 3.8 |
| .PRO | TurboIntegrator Process Definition File | 3.8 |
| .DTHUMB | Android Data Thumbnail | 3.7 |
| .DIAGCAB | Troubleshooting Pack Cabinet File | 3.7 |
| .HDMP | Windows Heap Dump | 3.7 |
| .CAT | Windows Catalog File | 3.7 |
| .MBN | Multi Boot Image | 3.7 |
| .POL | Windows Policy File | 3.7 |
| .DRPM | Delta RPM File | 3.7 |
| .PPD | PostScript Printer Description File | 3.7 |
| .NB0 | Device Boot Loader Image | 3.7 |
| .AOS | ARCHOS PCtablet Firmware File | 3.7 |
| .SHD | Windows Print Job Shadow File | 3.7 |
| .SDT | Siemens Desktop Theme File | 3.7 |
| .CPL | Windows Control Panel Item | 3.7 |
| .AX | DirectShow Filter | 3.7 |
| .CHS | Windows Chinese Noise-Word List File | 3.7 |
| .BIO | BIOS File | 3.7 |
| .SAVEDSEARCH | Spotlight Saved Search | 3.7 |
| .CANNEDSEARCH | Apple Predefined Search | 3.7 |
| .1 | Unix Section 1 Manual Page | 3.6 |
| .VXD | Virtual Device Driver | 3.6 |
| .JOB | Windows Task Scheduler Job File | 3.6 |
| .NLS | Microsoft National Language Support File | 3.6 |
| .CNT | Help Contents File | 3.6 |
| .8CU | TI-84 Plus C Operating System File | 3.6 |
| .WPX | Printer Description File | 3.6 |
| .SBF | Android System File | 3.6 |
| .ADML | Group Policy Language-Specific Administrative Template | 3.6 |
| .KEXT | Mac OS X Kernel Extension | 3.6 |
| .HLP | Windows Help File | 3.6 |
| .FPBF | Mac OS X Burn Folder | 3.6 |
| .CM0012 | Configuration Management File | 3.6 |
| .LST | GRUB Boot List File | 3.6 |
| .IDX | Index File | 3.6 |
| .8XU | TI-83 and TI-84 Plus Operating System File | 3.6 |
| .PRF | Windows System File | 3.5 |
| .CRASH | Mac OS X Crash Log File | 3.5 |
| .CONFIGPROFILE | Apple Configuration Profile | 3.5 |
| .SQM | Service Quality Monitoring File | 3.5 |
| .CHG | Windows Net Logon File | 3.5 |
| .SCHEMAS | GConf Schema Definition File | 3.5 |
| .DFU | iOS DFU File | 3.5 |
| .CPQ | Compaq OEM Disc Configuration File | 3.5 |
| .IME | Windows Input Method Editor File | 3.5 |
| .PANIC | Kernel Panic File | 3.5 |
| .4 | Unix Section 4 Manual Page | 3.5 |
| .TDZ | Drobo Firmware File | 3.5 |
| .LEX | Spelling Dictionary File | 3.5 |
| .WLU | Windows Legacy Update | 3.5 |
| .TRASHINFO | Linux Trash Metadata File | 3.5 |
| .EMERALD | Emerald Theme | 3.5 |
| .NTFS | NTFS Partition File | 3.5 |
| .GRP | Windows Program Manager Group | 3.5 |
| .SWP | Swap File | 3.5 |
| .SHSH | iPhone/iPod Touch SHSH Blob File | 3.5 |
| .386 | Windows Virtual Device Driver | 3.5 |
| .DATABASE_UUID | Android Stale Thumbnails Identifier | 3.5 |
| .2FS | Puppy Linux Save State File | 3.5 |
| .WER | Windows Error Report | 3.5 |
| .ODEX | Optimized Dalvik Executable | 3.4 |
| .LOG2 | Windows Registry Hive Log 2 File | 3.4 |
| .BLF | CLFS Base Log File | 3.4 |
| .SAVER | Mac OS X Screen Saver | 3.4 |
| .PS2 | Microsoft Search Catalog Index File | 3.4 |
| .HCD | Samsung Android Firmware File | 3.4 |
| .HHC | HTML Help Table of Contents | 3.4 |
| .ADV | Audio Driver File | 3.4 |
| .KO | Linux Kernel Module File | 3.4 |
| .CHK | Netgear Router Firmware File | 3.3 |
| .0 | Android CA Digital Certificate | 3.3 |
| .ICL | Windows Icon Library File | 3.3 |
| .IPOD | Rockbox Firmware File | 3.3 |
| .METADATA_NEVER_INDEX | Spotlight Never Index File | 3.3 |
| .THA | Windows Thai Noise-Words List File | 3.3 |
| .IM4P | IMG4 Payload File | 3.3 |
| .PROFILE | Bash Shell Profile | 3.3 |
| .DIMAX | DiMAX Firmware Image File | 3.3 |
| .PROVISIONPROFILE | Apple Provision Profile | 3.3 |
| .STR | Windows Screensaver File | 3.3 |
| .PRINTEREXPORT | Windows Printer Migration File | 3.3 |
| .FLG | Puppy Linux Partition Flag File | 3.3 |
| .PID | Creative Driver File | 3.3 |
| .CHT | Windows Chinese Traditional Noise-Word List File | 3.3 |
| .NETWORKCONNECT | Apple Network Connect Document | 3.3 |
| .BMK | Windows Help Bookmarks | 3.3 |
| .PFX | PKCS #12 Certificate File | 3.3 |
| .RUF | Samsung DVD and Blu-ray Player Firmware File | 3.3 |
| .CPI | Codepage Information File | 3.3 |
| .MI4 | Audio Player Firmware File | 3.3 |
| .MSSTYLE | Windows XP Unsigned Style | 3.3 |
| .BOM | Mac OS X Bill of Materials File | 3.3 |
| .FFO | Find Fast Document Properties Cache | 3.3 |
| .NBH | ROM Update Utility Image File | 3.3 |
| .ATAHD | ATA Hard Drive Flag File | 3.3 |
| .XRM-MS | Microsoft Security Certificate | 3.2 |
| .PRT | Printer Driver File | 3.2 |
| .EVTX | Windows 7 Event Log File | 3.2 |
| .CAP | ASUS BIOS Update File | 3.2 |
| .MYDOCS | Send To My Documents | 3.2 |
| .KS | Kickstart File | 3.1 |
| .BK2 | Windows Indexing Service Data File | 3.1 |
| .SPL | Windows Print Spool File | 3.1 |
| .MUM | Windows Vista Update Package | 3.1 |
| .CUSTOMDESTINATIONS-MS | Windows Jump List File | 3.1 |
| .CPR | Windows Phone Display Settings File | 3.1 |
| .THUMBNAILS | Android Thumbnails Folder | 3.1 |
| .WGZ | S60 Web Runtime Widget Package | 3.0 |
| .SCF | Windows Explorer Command | 3.0 |
| .CMO | ASUS BIOS File | 3.0 |
| .FTR | IRIX File Type Rules File | 3.0 |
| .SEFW | Secure Element Firmware | 3.0 |
| .TBRES | Microsoft Store TokenBroker Cache File | 3.0 |
| .KC | macOS Kernel Extension Boot File | 3.0 |
| .SPRX | Signed PlayStation Relocatable Executable | 3.0 |
| .ME | Puppy Linux Partition Flag File | 3.0 |
| .HPJ | Help Project File | 3.0 |
| .HSH | Windows Catalog Search Index File | 3.0 |
| .EVT | Windows Event Viewer Log File | 3.0 |
| .PS1 | Microsoft Indexing Service Data File | 3.0 |
| .BK1 | Windows Indexing Service File | 3.0 |
| .DLX | Renamed DLL File | 3.0 |
| .RFW | Rockchip Firmware File | 3.0 |
| .SIN | Sony Xperia Firmware File | 3.0 |
| .IMG2 | iPhone Firmware Image | 3.0 |
| .DIAGPKG | Troubleshooting Pack File | 3.0 |
| .MEM | Parallels Desktop Memory Dump File | 3.0 |
| .B84 | TI-84 Plus CE Bundle Image | 3.0 |
| .GMMP | WCS Gamut Map Model Profile | 3.0 |
| .UTV | SmartCast TV Firmware Update | 3.0 |
| .ESCOPY | ES File Explorer File Manager Temporary File | 3.0 |
| .JOURNAL | Linux Journald Event Log | 3.0 |
| .MUN | Windows System Resource Archive | 3.0 |
| .UCE | Windows UCE System File | 3.0 |
| .KDZ | LG Mobile Device Firmware | 3.0 |
| .XFB | Xserve RAID Firmware Binary File | 3.0 |
| .IFW | INTUS Firmware File | 3.0 |
| .EFIRES | EFI Image File | 3.0 |
| .TRASHES | macOS USB Flash Drive Trash Folder | 2.9 |
| .SO.0 | Unix Shared Library File | 2.9 |
| .GRL | Windows Update Status File | 2.9 |
| .SCAP | EFI Firmware File | 2.9 |
| .DSS | DCC Active Designer File | 2.8 |
| .AUTOMATICDESTINATIONS-MS | Windows Jump List File | 2.8 |
| .FFA | Find Fast Status File | 2.8 |
| .FL1 | Lenovo BIOS Update File | 2.8 |
| .LPD | LPD Daemon Print Permissions File | 2.8 |
| .DEVICEMETADATA-MS | Device Metadata Package | 2.8 |
| .KBD | Keyboard Layout Script | 2.8 |
| .PPM | Post Programmable Memory File | 2.7 |
| .RC2 | Samsung Mobile Device Firmware File | 2.7 |
| .OZIP | OPPO Smartphone Firmware Update | 2.7 |
| .VDEX | Validated Dalvik Executable File | 2.7 |
| .LM | Language Model File | 2.7 |
| .FTS | Full Text Search | 2.7 |
| .DOCK | Mac OS X Dock Extra | 2.6 |
| .JETKEY | iOS Support Jet File | 2.6 |
| .IDI | EVA Controller Event Log | 2.6 |
| .SB | Slax Bundle | 2.6 |
| .BUD | Binary Printer Description File | 2.6 |
| .VGD | Generic CADD VGA Driver | 2.6 |
| .DIC | Windows 10 Custom Spelling Dictionary | 2.5 |
| .DIAGCFG | Troubleshooting Pack Configuration File | 2.5 |
| .RCO | PlayStation Portable Resource File | 2.5 |
| .IPTHEME | IconPackager Raw Theme File | 2.5 |
| .WPH | Phoenix BIOS File | 2.5 |
| .PUSH_DEVICEID | Android Device Identification File | 2.5 |
| .7 | Unix Section 7 Manual Page | 2.5 |
| .2 | Unix Section 2 Manual Page | 2.5 |
| .3 | Unix Section 3 Manual Page | 2.5 |
| .LPD | Lookout Protocol Driver File | 2.5 |
| .6 | Unix Section 6 Manual Page | 2.5 |
| .5 | Unix Section 5 Manual Page | 2.5 |
| .RS | Windows Rating System File | 2.4 |
| .QKY | Quirky Kernel | 2.4 |
| .KWI | Toyota Entune Update File | 2.4 |
| .DYC | Xerox Printer Driver Configuration File | 2.4 |
| .JPN | Windows Japanese Noise-Word List File | 2.4 |
| .FID | Microsoft Catalog Indexing Service File | 2.3 |
| .LOCALIZED | macOS Directory Localization File | 2.3 |
| .TA | Sony Firmware File | 2.3 |
| .KL | Android Key Layout File | 2.3 |
| .KEY | Android Passcode File | 2.3 |
| .SPX | System Profiler XML Report | 2.3 |
| .INTERNETCONNECT | Apple Internet Connect Document | 2.3 |
| .FFL | Find Fast Document List | 2.0 |
| .RCV | BIOS Recovery File | 2.0 |
| .89U | TI-89 Titanium Operating System File | 2.0 |
| .DUB | Windows Spelling Dictionary Identifier | 2.0 |
| .MMV | Magnex Firmware File | 2.0 |
| .ROKU | Roku TV Firmware Update | 2.0 |
| .IUS | InfoTMIC Firmware Update File | 2.0 |
| .TCO2 | TI-Nspire CX II Operating System File | 2.0 |
| .ITS | Internet Document Set | 2.0 |
| .XGF | Xiegu G Series Firmware Update | 2.0 |
| .B83 | TI-83 Premium CE Bundle Image | 2.0 |
| .KOR | Windows Korean Noise-Words List File | 2.0 |
| .BBFW | Apple Baseband Firmware Update | 2.0 |
| .CDMP | WCS Device Model Profile | 2.0 |
| .FTG | Full Text Group | 2.0 |
| .ANN | Windows Help Annotations | 1.8 |
| .8 | Unix Section 8 Manual Page | 1.8 |
| .REGLNK | Registry Editor Shortcut File | 1.8 |
| .HELP | Mac OS X Help Book | 1.6 |
| .DIFFBASE | Windows Diagnostics Tracking Diffbase File | 1.5 |
| .RVP | Sharp Blu-ray Player Firmware File | 1.0 |
| .SELF | Signed Executable and Linkable Format | 1.0 |