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