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 |
|---|---|---|
| .AML | ACPI Machine Language File | 4.5 |
| .WDGT | Dashboard Widget | 4.4 |
| .REG | Registry File | 4.4 |
| .ADMX | Group Policy Administrative Template File | 4.4 |
| .CUR | Windows Cursor | 4.3 |
| .73U | TI-73 Explorer Operating System File | 4.3 |
| .REGTRANS-MS | Registry Transaction Log File | 4.3 |
| .ICNS | macOS Icon Resource File | 4.3 |
| .FTF | FlashTool Firmware File | 4.3 |
| .ICONPACKAGE | IconPackager Theme File | 4.3 |
| .CLB | COM+ Catalog File | 4.3 |
| .ANI | Windows Animated Cursor | 4.3 |
| .DLL | Dynamic Link Library | 4.3 |
| .DESKTHEMEPACK | Windows 8 Desktop Theme Pack File | 4.3 |
| .SEARCHCONNECTOR-MS | Windows Search Connector File | 4.2 |
| .HTT | Hypertext Template | 4.2 |
| .DESKLINK | Desktop Shortcut | 4.2 |
| .LNK | Windows Shortcut | 4.2 |
| .VGA | VGA Display Driver | 4.2 |
| .HVE | Windows Registry Hive File | 4.2 |
| .ITEMDATA-MS | Windows 8 Start Screen Item Data File | 4.2 |
| .DMP | Windows Memory Dump | 4.2 |
| .NFO | System Information File | 4.2 |
| .DVD | DOS Device Driver | 4.2 |
| .MDMP | Windows Minidump | 4.2 |
| .PK2 | Silkroad Online Game Data File | 4.2 |
| .RMT | Router Firmware File | 4.2 |
| .VX_ | Compressed Virtual Device Driver File | 4.2 |
| .THEME | Microsoft Plus! Desktop Theme | 4.2 |
| .QVM | Q Virtual Machine | 4.2 |
| .NT | Windows NT Startup File | 4.1 |
| .PCK | System Center Configuration Manager Package File | 4.1 |
| .EBD | Windows EBD System File | 4.1 |
| .INF_LOC | Windows Driver Information Cache File | 4.1 |
| .ICO | Icon File | 4.1 |
| .SYS | Windows System File | 4.1 |
| .LIBRARY-MS | Windows Library Description File | 4.1 |
| .HIV | Windows Registry Hive File | 4.1 |
| .SFCACHE | ReadyBoost Cache File | 4.1 |
| .RC1 | Samsung Mobile Device Firmware File | 4.1 |
| .SCR | Windows Screensaver | 4.1 |
| .ASEC | Android Secure Application File | 4.1 |
| .PROP | Android Build Properties File | 4.1 |
| .MANIFEST | Windows Application Manifest File | 4.1 |
| .BASH_HISTORY | Bash History File | 4.0 |
| .ION | File Description File | 4.0 |
| .PAT | DiskStation Manager Installation File | 4.0 |
| .ELF | Executable and Linkable Format File | 4.0 |
| .BIN | Router Firmware File | 4.0 |
| .CAB | Windows Cabinet File | 4.0 |
| .ETL | Microsoft Event Trace Log File | 4.0 |
| .CPL | Windows Control Panel Item | 4.0 |
| .TIMER | Systemd Unit Configuration File | 4.0 |
| .LOCKFILE | Mac OS X PLIST Lock File | 4.0 |
| .CGZ | Linux Drivers Archive | 4.0 |
| .FFX | Microsoft Find Fast Index | 4.0 |
| .LOG1 | Windows Registry Hive Log File | 4.0 |
| .FOTA | Firmware Over-the-Air File | 4.0 |
| .CI | Windows Content Indexer Catalog File | 4.0 |
| .ZONE.IDENTIFIER | Windows Zone Identifier File | 4.0 |
| .PREFPANE | Mac OS X System Preference Pane | 4.0 |
| .MUI | Multilingual User Interface File | 4.0 |
| .000 | Indexing Service Data File | 4.0 |
| .MENU | macOS Menu Extra | 4.0 |
| .NLT | Windows Transliteration File | 4.0 |
| .EDJ | Enlightenment Theme File | 4.0 |
| .SERVICE | Systemd Service Unit File | 4.0 |
| .PWL | Windows Password List | 4.0 |
| .FIRM | Boot9Strap 3DS Firmware File | 4.0 |
| .MAPIMAIL | Send To Mail Recipient | 4.0 |
| .DAT | Windows Registry Hive File | 4.0 |
| .MSC | Microsoft Management Console Snap-in Control File | 4.0 |
| .H1S | Windows Assistance Platform Help File | 4.0 |
| .ADM | Administrative Template File | 4.0 |
| .FX | ReadyBoot Trace File | 3.9 |
| .WDF | Windows Driver Foundation File | 3.9 |
| .SDB | Custom Application Compatibility Database | 3.9 |
| .MOD | GRUB Module | 3.9 |
| .LFS | Samsung Phone params.lfs File | 3.9 |
| .MLC | Microsoft Language Interface Pack | 3.9 |
| .BASH_PROFILE | Bash Interactive Login Shell File | 3.9 |
| .MSSTYLES | Windows XP Style | 3.9 |
| .CM0013 | Samsung Smart TV Index File | 3.9 |
| .MOBILECONFIG | Apple Mobile Configuration File | 3.8 |
| .PNF | Precompiled INF File | 3.8 |
| .SYS | Motorola Driver File | 3.8 |
| .PIT | Samsung Phone Firmware File | 3.8 |
| .EFI | Extensible Firmware Interface File | 3.8 |
| .MTZ | MIUI Theme | 3.8 |
| .MBR | Master Boot Record File | 3.8 |
| .DRV | Device Driver | 3.8 |
| .C32 | Syslinux COM32 Module | 3.8 |
| .POL | Windows Policy File | 3.8 |
| .WEBPNP | Web Point and Print File | 3.8 |
| .SBN | Cisco IP Phone Firmware File | 3.8 |
| .HHK | HTML Help Index | 3.8 |
| .GROUP | Windows Contacts Group File | 3.8 |
| .0 | Shared Library Link File | 3.8 |
| .208 | ASUS Notebook BIOS 208 Update File | 3.8 |
| .BIO | BIOS File | 3.8 |
| .DIAGCAB | Troubleshooting Pack Cabinet File | 3.8 |
| .BCD | Windows Boot Configuration Data File | 3.8 |
| .BASHRC | Bash Non-Interactive Login Shell File | 3.8 |
| .INS | Internet Naming Service File | 3.8 |
| .PLASMOID | Plasma Widget | 3.8 |
| .3FS | Puppy Linux Save State File | 3.8 |
| .PDR | Windows Port Driver | 3.8 |
| .IMG3 | iPhone IMG3 File | 3.8 |
| .MSP | Windows Installer Patch | 3.7 |
| .DRPM | Delta RPM File | 3.7 |
| .PRF | Windows System File | 3.7 |
| .AOS | ARCHOS PCtablet Firmware File | 3.7 |
| .SDT | Siemens Desktop Theme File | 3.7 |
| .CHS | Windows Chinese Noise-Word List File | 3.7 |
| .DTHUMB | Android Data Thumbnail | 3.7 |
| .CNT | Help Contents File | 3.7 |
| .SAVEDSEARCH | Spotlight Saved Search | 3.7 |
| .DIT | Active Directory Information Tree File | 3.7 |
| .CANNEDSEARCH | Apple Predefined Search | 3.7 |
| .IOPLIST | Mac OS X IOPLIST File | 3.7 |
| .VXD | Virtual Device Driver | 3.6 |
| .NLS | Microsoft National Language Support File | 3.6 |
| .JOB | Windows Task Scheduler Job File | 3.6 |
| .PPD | PostScript Printer Description File | 3.6 |
| .MBN | Multi Boot Image | 3.6 |
| .WPX | Printer Description File | 3.6 |
| .SBF | Android System File | 3.6 |
| .SQM | Service Quality Monitoring File | 3.6 |
| .HDMP | Windows Heap Dump | 3.6 |
| .CAT | Windows Catalog File | 3.6 |
| .CRASH | Mac OS X Crash Log File | 3.6 |
| .MUI_CCCD5AE0 | Hid User Library | 3.6 |
| .DEV | Windows Device Driver File | 3.6 |
| .FPBF | Mac OS X Burn Folder | 3.6 |
| .BOM | Mac OS X Bill of Materials File | 3.6 |
| .LOG2 | Windows Registry Hive Log 2 File | 3.6 |
| .PROFILE | Bash Shell Profile | 3.6 |
| .LST | GRUB Boot List File | 3.6 |
| .NB0 | Device Boot Loader Image | 3.6 |
| .SHD | Windows Print Job Shadow File | 3.6 |
| .8XU | TI-83 and TI-84 Plus Operating System File | 3.6 |
| .KEY | Security Key | 3.6 |
| .ADML | Group Policy Language-Specific Administrative Template | 3.6 |
| .HLP | Windows Help File | 3.5 |
| .DFU | iOS DFU File | 3.5 |
| .SCHEMAS | GConf Schema Definition File | 3.5 |
| .PANIC | Kernel Panic File | 3.5 |
| .CHG | Windows Net Logon File | 3.5 |
| .IME | Windows Input Method Editor File | 3.5 |
| .TDZ | Drobo Firmware File | 3.5 |
| .CPQ | Compaq OEM Disc Configuration File | 3.5 |
| .GRP | Windows Program Manager Group | 3.5 |
| .SHSH | iPhone/iPod Touch SHSH Blob File | 3.5 |
| .KS | Kickstart File | 3.5 |
| .SWP | Swap File | 3.5 |
| .CM0012 | Configuration Management File | 3.5 |
| .IDX | Index File | 3.5 |
| .386 | Windows Virtual Device Driver | 3.5 |
| .2FS | Puppy Linux Save State File | 3.5 |
| .KEXT | Mac OS X Kernel Extension | 3.5 |
| .FLG | Puppy Linux Partition Flag File | 3.4 |
| .KO | Linux Kernel Module File | 3.4 |
| .HHC | HTML Help Table of Contents | 3.4 |
| .PS2 | Microsoft Search Catalog Index File | 3.4 |
| .HCD | Samsung Android Firmware File | 3.4 |
| .CHK | Netgear Router Firmware File | 3.4 |
| .ODEX | Optimized Dalvik Executable | 3.4 |
| .WER | Windows Error Report | 3.4 |
| .ADV | Audio Driver File | 3.4 |
| .DIMAX | DiMAX Firmware Image File | 3.3 |
| .THA | Windows Thai Noise-Words List File | 3.3 |
| .CPI | Codepage Information File | 3.3 |
| .8CU | TI-84 Plus C Operating System File | 3.3 |
| .IM4P | IMG4 Payload File | 3.3 |
| .ICL | Windows Icon Library File | 3.3 |
| .PRINTEREXPORT | Windows Printer Migration File | 3.3 |
| .PRO | TurboIntegrator Process Definition File | 3.3 |
| .NTFS | NTFS Partition File | 3.3 |
| .PFX | PKCS #12 Certificate File | 3.3 |
| .BMK | Help Bookmarks | 3.3 |
| .CHT | Windows Chinese Traditional Noise-Word List File | 3.3 |
| .METADATA_NEVER_INDEX | Spotlight Never Index File | 3.3 |
| .BLF | CLFS Base Log File | 3.3 |
| .MI4 | Audio Player Firmware File | 3.3 |
| .ATAHD | ATA Hard Drive Flag File | 3.3 |
| .NBH | ROM Update Utility Image File | 3.3 |
| .FFO | Find Fast Document Properties Cache | 3.3 |
| .TRX_DLL | Windows Startup File | 3.3 |
| .MSSTYLE | Windows XP Unsigned Style | 3.3 |
| .SO.0 | Unix Shared Library File | 3.2 |
| .PID | Creative Driver File | 3.2 |
| .XRM-MS | Microsoft Security Certificate | 3.2 |
| .PRT | Printer Driver File | 3.2 |
| .STR | Windows Screensaver File | 3.2 |
| .SAVER | Mac OS X Screen Saver | 3.2 |
| .CUSTOMDESTINATIONS-MS | Windows Jump List File | 3.2 |
| .THUMBNAILS | Android Thumbnails Folder | 3.1 |
| .CONFIGPROFILE | Apple Configuration Profile | 3.1 |
| .BK2 | Windows Indexing Service Data File | 3.1 |
| .SPL | Windows Print Spool File | 3.1 |
| .RUF | Samsung DVD and Blu-ray Player Firmware File | 3.1 |
| .MUM | Windows Vista Update Package | 3.1 |
| .CAP | ASUS BIOS Update File | 3.1 |
| .CPR | Windows Phone Display Settings File | 3.1 |
| .PS1 | Microsoft Indexing Service Data File | 3.1 |
| .EVTX | Windows 7 Event Log File | 3.1 |
| .HSH | Windows Catalog Search Index File | 3.0 |
| .BK1 | Windows Indexing Service File | 3.0 |
| .DLX | Renamed DLL File | 3.0 |
| .CMO | ASUS BIOS File | 3.0 |
| .ME | Puppy Linux Partition Flag File | 3.0 |
| .SIN | Sony Xperia Firmware File | 3.0 |
| .0 | Android CA Digital Certificate | 3.0 |
| .UCE | Windows UCE System File | 3.0 |
| .LPD | LPD Daemon Print Permissions File | 3.0 |
| .DIC | Windows 10 Custom Spelling Dictionary | 3.0 |
| .SHSH2 | iOS SHSH Blob | 3.0 |
| .MEM | Parallels Desktop Memory Dump File | 3.0 |
| .B83 | TI-83 Premium CE Bundle Image | 3.0 |
| .B84 | TI-84 Plus CE Bundle Image | 3.0 |
| .MUN | Windows System Resource Archive | 3.0 |
| .GMMP | WCS Gamut Map Model Profile | 3.0 |
| .KDZ | LG Mobile Device Firmware | 3.0 |
| .DIAGPKG | Troubleshooting Pack File | 3.0 |
| .DATABASE_UUID | Android Stale Thumbnails Identifier | 3.0 |
| .ESCOPY | ES File Explorer File Manager Temporary File | 3.0 |
| .RFW | Rockchip Firmware File | 3.0 |
| .HPJ | Help Project File | 3.0 |
| .IFW | INTUS Firmware File | 3.0 |
| .EFIRES | EFI Image File | 3.0 |
| .PROVISIONPROFILE | Apple Provision Profile | 3.0 |
| .XFB | Xserve RAID Firmware Binary File | 2.9 |
| .SCAP | EFI Firmware File | 2.9 |
| .SCF | Windows Explorer Command | 2.9 |
| .GRL | Windows Update Status File | 2.9 |
| .TRASHES | macOS USB Flash Drive Trash Folder | 2.8 |
| .FFA | Find Fast Status File | 2.8 |
| .FL1 | Lenovo BIOS Update File | 2.8 |
| .DEVICEMETADATA-MS | Device Metadata Package | 2.8 |
| .DYC | Xerox Printer Driver Configuration File | 2.8 |
| .KBD | Keyboard Layout Script | 2.8 |
| .PPM | Post Programmable Memory File | 2.7 |
| .OZIP | OPPO Smartphone Firmware Update | 2.7 |
| .AUTOMATICDESTINATIONS-MS | Windows Jump List File | 2.7 |
| .RC2 | Samsung Mobile Device Firmware File | 2.7 |
| .DSS | DCC Active Designer 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 |
| .IPOD | Rockbox Firmware File | 2.5 |
| .RCO | PlayStation Portable Resource File | 2.5 |
| .IPTHEME | IconPackager Raw Theme File | 2.5 |
| .FTS | Full Text Search | 2.5 |
| .LPD | Lookout Protocol Driver File | 2.5 |
| .WPH | Phoenix BIOS File | 2.5 |
| .LOCALIZED | macOS Directory Localization File | 2.5 |
| .NETWORKCONNECT | Apple Network Connect Document | 2.5 |
| .MYDOCS | Send To My Documents | 2.5 |
| .RS | Windows Rating System File | 2.4 |
| .QKY | Quirky Kernel | 2.4 |
| .JPN | Windows Japanese Noise-Word List File | 2.4 |
| .FID | Microsoft Catalog Indexing Service File | 2.3 |
| .WGZ | S60 Web Runtime Widget Package | 2.3 |
| .TA | Sony Firmware File | 2.3 |
| .SPX | System Profiler XML Report | 2.3 |
| .IUS | InfoTMIC Firmware Update File | 2.0 |
| .EVT | Windows Event Viewer Log File | 2.0 |
| .KOR | Windows Korean Noise-Words List File | 2.0 |
| .RCV | BIOS Recovery File | 2.0 |
| .MMV | Magnex Firmware File | 2.0 |
| .TCO2 | TI-Nspire CX II Operating System File | 2.0 |
| .ROKU | Roku TV Firmware Update File | 2.0 |
| .89U | TI-89 Titanium Operating System File | 2.0 |
| .WLU | Windows Legacy Update | 2.0 |
| .DOCK | Mac OS X Dock Extra | 2.0 |
| .DUB | Windows Spelling Dictionary Identifier | 2.0 |
| .LM | Language Model File | 2.0 |
| .VDEX | Validated Dalvik Executable File | 2.0 |
| .TRASHINFO | Linux Trash Metadata File | 2.0 |
| .LEX | Spelling Dictionary File | 2.0 |
| .FFL | Find Fast Document List | 2.0 |
| .REGLNK | Registry Editor Shortcut File | 2.0 |
| .FTG | Full Text Group | 2.0 |
| .EMERALD | Emerald Theme | 2.0 |
| .CDMP | WCS Device Model Profile | 2.0 |
| .KWI | Toyota Entune Update File | 2.0 |
| .ANN | Help Annotations | 1.8 |
| .HELP | Mac OS X Help Book | 1.6 |
| .DIFFBASE | Windows Diagnostics Tracking Diffbase File | 1.5 |
| .INTERNETCONNECT | Apple Internet Connect Document | 1.3 |
| .ITS | Internet Document Set | 1.0 |
| .RVP | Sharp Blu-ray Player Firmware File | 1.0 |
| .SPRX | Signed PlayStation Relocatable Executable | 1.0 |
| .SELF | Signed Executable and Linkable Format | 1.0 |