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 |
|---|---|---|
| .ADMX | Group Policy Administrative Template File | 4.4 |
| .RMT | Router Firmware File | 4.4 |
| .REG | Registry File | 4.4 |
| .VGA | VGA Display Driver | 4.3 |
| .SHSH2 | iOS SHSH Blob | 4.3 |
| .AML | ACPI Machine Language File | 4.3 |
| .CUR | Windows Cursor Image | 4.3 |
| .ITEMDATA-MS | Windows 8 Start Screen Item Data File | 4.3 |
| .ANI | Windows Animated Cursor | 4.3 |
| .CLB | COM+ Catalog File | 4.3 |
| .WDGT | Dashboard Widget | 4.3 |
| .SERVICE | Systemd Service Unit File | 4.3 |
| .REGTRANS-MS | Registry Transaction Log File | 4.3 |
| .NT | Windows NT Startup File | 4.3 |
| .ICNS | macOS Icon Resource | 4.2 |
| .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 |
| .SEARCHCONNECTOR-MS | Windows Search Connector File | 4.2 |
| .HVE | Windows Registry Hive File | 4.2 |
| .PK2 | Silkroad Online Game Data File | 4.2 |
| .DVD | DOS Device Driver | 4.2 |
| .DMP | Windows Memory Dump | 4.2 |
| .DESKLINK | Desktop Shortcut | 4.2 |
| .LNK | Windows Shortcut | 4.2 |
| .THEME | Microsoft Plus! Desktop Theme | 4.2 |
| .HIV | Windows Registry Hive File | 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 |
| .HTT | Hypertext Template | 4.1 |
| .LOCKFILE | Mac OS X PLIST Lock File | 4.1 |
| .SYS | Windows System File | 4.1 |
| .ELF | Executable and Linkable Format File | 4.1 |
| .LIBRARY-MS | Windows Library Description File | 4.1 |
| .PCK | System Center Configuration Manager Package File | 4.1 |
| .SFCACHE | ReadyBoost Cache 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 |
| .RC1 | Samsung Mobile Device Firmware File | 4.1 |
| .FTF | FlashTool Firmware File | 4.1 |
| .MANIFEST | Windows Application Manifest File | 4.1 |
| .PROP | Android Build Properties File | 4.1 |
| .NFO | System Information File | 4.1 |
| .000 | Indexing Service Data File | 4.0 |
| .MUI | Multilingual User Interface File | 4.0 |
| .ETL | Microsoft Event Trace Log File | 4.0 |
| .BIN | Router Firmware File | 4.0 |
| .TIMER | Systemd Unit Configuration File | 4.0 |
| .MAPIMAIL | Send To Mail Recipient | 4.0 |
| .BASH_HISTORY | Bash History File | 4.0 |
| .CGZ | Linux Drivers Archive | 4.0 |
| .PREFPANE | Mac OS X System Preference Pane | 4.0 |
| .ZONE.IDENTIFIER | Windows Zone Identifier File | 4.0 |
| .CI | Windows Content Indexer Catalog File | 4.0 |
| .MSC | Microsoft Management Console Snap-in Control File | 4.0 |
| .EDJ | Enlightenment Theme File | 4.0 |
| .MOD | GRUB Module | 4.0 |
| .MENU | macOS Menu Extra | 4.0 |
| .PWL | Windows Password List | 4.0 |
| .H1S | Windows Assistance Platform Help File | 4.0 |
| .DAT | Windows Registry Hive File | 4.0 |
| .CM0013 | Samsung Smart TV Index File | 4.0 |
| .ADM | Administrative Template File | 4.0 |
| .SCR | Windows Screensaver | 3.9 |
| .EFI | Extensible Firmware Interface File | 3.9 |
| .FX | ReadyBoot Trace File | 3.9 |
| .LOG1 | Windows Registry Hive Log File | 3.9 |
| .CAB | Windows Cabinet File | 3.9 |
| .WDF | Windows Driver Foundation File | 3.9 |
| .BASHRC | Bash Non-Interactive Login Shell 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 |
| .MSSTYLES | Windows XP Style | 3.9 |
| .FOTA | Firmware Over-the-Air File | 3.9 |
| .PIT | Samsung Phone Firmware File | 3.8 |
| .MOBILECONFIG | Apple Mobile Configuration File | 3.8 |
| .C32 | Syslinux COM32 Module | 3.8 |
| .SYS | Motorola Cell Phone Driver | 3.8 |
| .PNF | Precompiled INF File | 3.8 |
| .TRX_DLL | Windows Startup File | 3.8 |
| .73U | TI-73 Explorer Operating System File | 3.8 |
| .MTZ | MIUI Theme | 3.8 |
| .SBN | Cisco IP Phone Firmware File | 3.8 |
| .HHK | HTML Help Index | 3.8 |
| .WEBPNP | Web Point and Print 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 |
| .DRV | Device Driver | 3.8 |
| .BASH_PROFILE | Bash Interactive Login Shell File | 3.8 |
| .PDR | Windows Port Driver | 3.8 |
| .DIT | Active Directory Information Tree File | 3.8 |
| .DTHUMB | Android Data Thumbnail | 3.8 |
| .MBR | Master Boot Record File | 3.8 |
| .INS | Internet Naming Service File | 3.8 |
| .IMG3 | iPhone IMG3 File | 3.8 |
| .PLASMOID | Plasma Widget | 3.8 |
| .IOPLIST | Mac OS X IOPLIST File | 3.8 |
| .MUI_CCCD5AE0 | Hid User Library | 3.8 |
| .3FS | Puppy Linux Save State File | 3.8 |
| .PRO | TurboIntegrator Process Definition File | 3.8 |
| .DIAGCAB | Troubleshooting Pack Cabinet File | 3.7 |
| .HDMP | Windows Heap Dump | 3.7 |
| .CAT | Windows Catalog File | 3.7 |
| .POL | Windows Policy File | 3.7 |
| .DRPM | Delta RPM File | 3.7 |
| .PPD | PostScript Printer Description File | 3.7 |
| .AOS | ARCHOS PCtablet Firmware File | 3.7 |
| .SHD | Windows Print Job Shadow File | 3.7 |
| .NB0 | Device Boot Loader Image | 3.7 |
| .SDT | Siemens Desktop Theme File | 3.7 |
| .CPL | Windows Control Panel Item | 3.7 |
| .PAT | DiskStation Manager Installation File | 3.7 |
| .AX | DirectShow Filter | 3.7 |
| .MSP | Windows Installer Patch | 3.7 |
| .BIO | BIOS File | 3.7 |
| .CHS | Windows Chinese Noise-Word List File | 3.7 |
| .SAVEDSEARCH | Spotlight Saved Search | 3.7 |
| .CANNEDSEARCH | Apple Predefined Search | 3.7 |
| .VXD | Virtual Device Driver | 3.6 |
| .1 | Unix Section 1 Manual Page | 3.6 |
| .MBN | Multi Boot Image | 3.6 |
| .JOB | Windows Task Scheduler Job File | 3.6 |
| .NLS | Microsoft National Language Support File | 3.6 |
| .SBF | Android System File | 3.6 |
| .CNT | Help Contents File | 3.6 |
| .WPX | Printer Description File | 3.6 |
| .8CU | TI-84 Plus C Operating System File | 3.6 |
| .KEXT | Mac OS X Kernel Extension | 3.6 |
| .CRASH | Mac OS X Crash Log File | 3.6 |
| .HLP | Windows Help File | 3.6 |
| .FPBF | Mac OS X Burn Folder | 3.6 |
| .CM0012 | Configuration Management File | 3.6 |
| .2FS | Puppy Linux Save State File | 3.6 |
| .IDX | Index File | 3.6 |
| .8XU | TI-83 and TI-84 Plus Operating System File | 3.6 |
| .CONFIGPROFILE | Apple Configuration Profile | 3.5 |
| .PRF | Windows System File | 3.5 |
| .PS2 | Microsoft Search Catalog Index File | 3.5 |
| .LOG2 | Windows Registry Hive Log 2 File | 3.5 |
| .SQM | Service Quality Monitoring File | 3.5 |
| .ADML | Group Policy Language-Specific Administrative Template | 3.5 |
| .CHG | Windows Net Logon File | 3.5 |
| .CPQ | Compaq OEM Disc Configuration File | 3.5 |
| .EMERALD | Emerald Theme | 3.5 |
| .PANIC | Kernel Panic File | 3.5 |
| .NTFS | NTFS Partition File | 3.5 |
| .DFU | iOS DFU File | 3.5 |
| .LEX | Spelling Dictionary File | 3.5 |
| .WLU | Windows Legacy Update | 3.5 |
| .TDZ | Drobo Firmware File | 3.5 |
| .SCHEMAS | GConf Schema Definition File | 3.5 |
| .IME | Windows Input Method Editor File | 3.5 |
| .4 | Unix Section 4 Manual Page | 3.5 |
| .GRP | Windows Program Manager Group | 3.5 |
| .JOURNAL | Linux Journald Event Log | 3.5 |
| .B84 | TI-84 Plus CE Bundle Image | 3.5 |
| .SWP | Swap File | 3.5 |
| .SHSH | iPhone/iPod Touch SHSH Blob File | 3.5 |
| .0 | Android CA Digital Certificate | 3.5 |
| .UTV | SmartCast TV Firmware Update | 3.5 |
| .FFX | Microsoft Find Fast Index | 3.5 |
| .386 | Windows Virtual Device Driver | 3.5 |
| .ODEX | Optimized Dalvik Executable | 3.5 |
| .LST | GRUB Boot List File | 3.5 |
| .WER | Windows Error Report | 3.5 |
| .DATABASE_UUID | Android Stale Thumbnails Identifier | 3.5 |
| .DEV | Windows Device Driver File | 3.4 |
| .BLF | CLFS Base Log File | 3.4 |
| .SAVER | Mac OS X Screen Saver | 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 |
| .TRASHINFO | Linux Trash Metadata File | 3.3 |
| .ICL | Windows Icon Library File | 3.3 |
| .GROUP | Windows Contacts Group File | 3.3 |
| .THA | Windows Thai Noise-Words List File | 3.3 |
| .IPOD | Rockbox Firmware File | 3.3 |
| .KDZ | LG Mobile Device Firmware | 3.3 |
| .IM4P | IMG4 Payload File | 3.3 |
| .PROVISIONPROFILE | Apple Provision Profile | 3.3 |
| .PRINTEREXPORT | Windows Printer Migration File | 3.3 |
| .2 | Unix Section 2 Manual Page | 3.3 |
| .DIMAX | DiMAX Firmware Image File | 3.3 |
| .DIC | Windows 10 Custom Spelling Dictionary | 3.3 |
| .STR | Windows Screensaver File | 3.3 |
| .METADATA_NEVER_INDEX | Spotlight Never Index File | 3.3 |
| .NLT | Windows Transliteration File | 3.3 |
| .PROFILE | Bash Shell Profile | 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 |
| .BMK | Windows Help Bookmarks | 3.3 |
| .NETWORKCONNECT | Apple Network Connect Document | 3.3 |
| .PFX | PKCS #12 Certificate File | 3.3 |
| .MUM | Windows Vista Update Package | 3.3 |
| .RUF | Samsung DVD and Blu-ray Player Firmware File | 3.3 |
| .NBH | ROM Update Utility Image File | 3.3 |
| .ATAHD | ATA Hard Drive Flag File | 3.3 |
| .MI4 | Audio Player Firmware File | 3.3 |
| .EVT | Windows Event Viewer Log File | 3.3 |
| .FFO | Find Fast Document Properties Cache | 3.3 |
| .CPI | Codepage Information File | 3.3 |
| .BOM | Mac OS X Bill of Materials File | 3.3 |
| .CAP | ASUS BIOS Update File | 3.2 |
| .XRM-MS | Microsoft Security Certificate | 3.2 |
| .PRT | Printer Driver File | 3.2 |
| .EVTX | Windows 7 Event Log File | 3.2 |
| .KBD | Keyboard Layout Script | 3.2 |
| .MYDOCS | Send To My Documents | 3.2 |
| .KS | Kickstart File | 3.1 |
| .SPL | Windows Print Spool File | 3.1 |
| .CUSTOMDESTINATIONS-MS | Windows Jump List File | 3.1 |
| .BK2 | Windows Indexing Service Data File | 3.1 |
| .CPR | Windows Phone Display Settings File | 3.1 |
| .MMV | Magnex Firmware File | 3.0 |
| .BK1 | Windows Indexing Service File | 3.0 |
| .SIN | Sony Xperia Firmware File | 3.0 |
| .CMO | ASUS BIOS File | 3.0 |
| .RCV | BIOS Recovery File | 3.0 |
| .DLX | Renamed DLL File | 3.0 |
| .SCF | Windows Explorer Command | 3.0 |
| .LM | Language Model File | 3.0 |
| .DEVICEMETADATA-MS | Device Metadata Package | 3.0 |
| .IMG2 | iPhone Firmware Image | 3.0 |
| .HPJ | Help Project File | 3.0 |
| .TBRES | Microsoft Store TokenBroker Cache File | 3.0 |
| .TRASH | ChromeOS Trash Storage | 3.0 |
| .MEM | Parallels Desktop Memory Dump File | 3.0 |
| .SPRX | Signed PlayStation Relocatable Executable | 3.0 |
| .GMMP | WCS Gamut Map Model Profile | 3.0 |
| .MUN | Windows System Resource Archive | 3.0 |
| .DIAGPKG | Troubleshooting Pack File | 3.0 |
| .ESCOPY | ES File Explorer File Manager Temporary File | 3.0 |
| .KC | macOS Kernel Extension Boot File | 3.0 |
| .WGZ | S60 Web Runtime Widget Package | 3.0 |
| .EFIRES | EFI Image File | 3.0 |
| .SEFW | Secure Element Firmware | 3.0 |
| .UCE | Windows UCE System File | 3.0 |
| .XFB | Xserve RAID Firmware Binary File | 3.0 |
| .HSH | Windows Catalog Search Index File | 3.0 |
| .RFW | Rockchip Firmware File | 3.0 |
| .SELF | Signed Executable and Linkable Format | 3.0 |
| .FTR | IRIX File Type Rules File | 3.0 |
| .IFW | INTUS Firmware File | 3.0 |
| .THUMBNAILS | Android Thumbnails Folder | 3.0 |
| .TRASHES | macOS USB Flash Drive Trash Folder | 2.9 |
| .SO.0 | Unix Shared Library File | 2.9 |
| .OZIP | OPPO Smartphone Firmware Update | 2.9 |
| .SCAP | EFI Firmware File | 2.9 |
| .PS1 | Microsoft Indexing Service Data File | 2.9 |
| .GRL | Windows Update Status File | 2.9 |
| .DOCK | Mac OS X Dock Extra | 2.8 |
| .DSS | DCC Active Designer File | 2.8 |
| .ME | Puppy Linux Partition Flag File | 2.8 |
| .AUTOMATICDESTINATIONS-MS | Windows Jump List File | 2.8 |
| .MSSTYLE | Windows XP Unsigned Style | 2.8 |
| .FL1 | Lenovo BIOS Update File | 2.8 |
| .LPD | LPD Daemon Print Permissions File | 2.8 |
| .FFA | Find Fast Status File | 2.8 |
| .3 | Unix Section 3 Manual Page | 2.8 |
| .RS | Windows Rating System File | 2.8 |
| .KEY | Android Passcode File | 2.7 |
| .PPM | Post Programmable Memory File | 2.7 |
| .FTS | Windows Help Full Text Search Index | 2.7 |
| .IUS | InfoTMIC Firmware Update File | 2.7 |
| .RC2 | Samsung Mobile Device Firmware File | 2.7 |
| .VDEX | Validated Dalvik Executable File | 2.7 |
| .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 |
| .DIAGCFG | Troubleshooting Pack Configuration File | 2.5 |
| .RCO | PlayStation Portable Resource File | 2.5 |
| .6 | Unix Section 6 Manual Page | 2.5 |
| .7 | Unix Section 7 Manual Page | 2.5 |
| .IPTHEME | IconPackager Raw Theme File | 2.5 |
| .PUSH_DEVICEID | Android Device Identification File | 2.5 |
| .5 | Unix Section 5 Manual Page | 2.5 |
| .LPD | Lookout Protocol Driver File | 2.5 |
| .WPH | Phoenix BIOS File | 2.5 |
| .KWI | Toyota Entune Update File | 2.4 |
| .QKY | Quirky Kernel | 2.4 |
| .DYC | Xerox Printer Driver Configuration File | 2.4 |
| .8 | Unix Section 8 Manual Page | 2.4 |
| .JPN | Windows Japanese Noise-Word List File | 2.4 |
| .FID | Microsoft Catalog Indexing Service File | 2.3 |
| .KL | Android Key Layout File | 2.3 |
| .TA | Sony Firmware File | 2.3 |
| .LOCALIZED | macOS Directory Localization File | 2.3 |
| .INTERNETCONNECT | Apple Internet Connect Document | 2.3 |
| .SPX | System Profiler XML Report | 2.3 |
| .KOR | Windows Korean Noise-Words List File | 2.0 |
| .MRM | MIUI Theme Metadata | 2.0 |
| .MRC | MIUI Theme Content Package | 2.0 |
| .ITS | Internet Document Set | 2.0 |
| .TCO2 | TI-Nspire CX II Operating System File | 2.0 |
| .BBFW | Apple Baseband Firmware Update | 2.0 |
| .B83 | TI-83 Premium CE Bundle Image | 2.0 |
| .ROKU | Roku TV Firmware Update | 2.0 |
| .XGF | Xiegu G Series Firmware Update | 2.0 |
| .FFL | Find Fast Document List | 2.0 |
| .DUB | Windows Spelling Dictionary Identifier | 2.0 |
| .FTG | Full Text Group | 2.0 |
| .89U | TI-89 Titanium Operating System File | 2.0 |
| .CDMP | WCS Device Model Profile | 2.0 |
| .ANN | Windows Help Annotations | 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 |
| .IM4M | IMG4 Manifest | 1.0 |