| Extension |
File Description |
|
Popularity |
| .386 | Windows Virtual Device Driver | | Rare |
| .8xu | TI-83 Plus Operating System File | | Uncommon |
| .adm | Administrative Template File | | Average |
| .ani | Windows Animated Cursor | | Common |
| .ann | Help Annotations | | Average |
| .aos | ARCHOS PCtablet Firmware File | | Uncommon |
| .bashrc | Bash Non-Interactive Login Shell File | | Common |
| .bash_history | Bash History File | | Common |
| .bash_profile | Bash Interactive Login Shell File | | Common |
| .bio | BIOS File | | Uncommon |
| .bmk | Help Bookmarks | | Uncommon |
| .bom | Mac OS X Bill of Materials File | | Uncommon |
| .cab | Windows Cabinet File | | Very Common |
| .cgz | Linux Drivers Archive | | Average |
| .clb | COM+ Catalog File | | Average |
| .cnt | Help Contents File | | Average |
| .cpi | Codepage Information File | | Average |
| .cpl | Windows Control Panel | | Very Common |
| .crash | Mac OS X Crash Log File | | Average |
| .cur | Windows Cursor | | Very Common |
| .desklink | Desktop Shortcut | | Average |
| .dev | Windows Device Driver File | | Average |
| .dll | Dynamic Link Library | | Very Common |
| .dlx | Renamed DLL File | | Rare |
| .dmp | Windows Memory Dump | | Very Common |
| .drv | Device Driver | | Very Common |
| .dss | DCC Active Designer File | | Average |
| .dvd | DOS Device Driver | | Average |
| .dyc | Xerox Printer Driver Configuration File | | Rare |
| .emerald | Emerald Theme | | Uncommon |
| .ffa | Find Fast Status File | | Uncommon |
| .ffl | Find Fast Document List | | Uncommon |
| .ffo | Find Fast Document Properties Cache | | Uncommon |
| .ffx | Microsoft Find Fast Index | | Average |
| .fpbf | Mac OS X Burn Folder | | Common |
| .ftg | Full Text Group | | Average |
| .fts | Full Text Search | | Average |
| .grl | Windows Update Status File | | Rare |
| .grp | Windows Program Manager Group | | Average |
| .hdmp | Windows Heap Dump | | Average |
| .hhc | HTML Help Table of Contents | | Average |
| .hhk | HTML Help Index | | Average |
| .hlp | Windows Help File | | Common |
| .hpj | Help Project File | | Average |
| .htt | Hypertext Template File | | Average |
| .icl | Windows Icon Library File | | Average |
| .icns | Mac OS X Icon Resource File | | Average |
| .ico | Icon File | | Common |
| .idx | Index File | | Average |
| .ins | Internet Naming Service File | | Average |
| .ion | 4DOS File Description | | Average |
| .its | Internet Document Set | | Average |
| .kbd | Keyboard Layout Script | | Average |
| .kext | Mac OS X Kernel Extension | | Average |
| .key | Security Key | | Common |
| .ko | Linux Kernel Module File | | Average |
| .lnk | File Shortcut | | Very Common |
| .log1 | Windows Registry Hive Log File | | Average |
| .log2 | Windows Registry Hive Log 2 File | | Average |
| .manifest | Windows Visual Styles File | | Average |
| .mapimail | Send To Mail Recipient | | Average |
| .mdmp | Windows Minidump | | Average |
| .mem | Parallels Desktop Memory Dump File | | Uncommon |
| .metadata_never_index | Spotlight Never Index File | | Uncommon |
| .mi4 | Audio Player Firmware File | | Average |
| .mobileconfig | Apple Mobile Configuration File | | Average |
| .msc | Microsoft Management Console Snap-in Control File | | Average |
| .msp | Windows Installer Patch | | Common |
| .msstyle | Windows XP Unsigned Style | | Uncommon |
| .msstyles | Windows XP Style | | Average |
| .mui | Multilingual User Interface File | | Average |
| .mum | Windows Vista Update Package | | Average |
| .mydocs | Send To My Documents | | Average |
| .nfo | System Information File | | Average |
| .nls | Microsoft National Language Support File | | Average |
| .nt | Windows NT Startup File | | Average |
| .p7b | PKCS #7 Certificate File | | Average |
| .panic | Kernel Panic File | | Uncommon |
| .pdr | Windows Port Driver | | Average |
| .pfx | PKCS #12 Certificate File | | Average |
| .pid | Creative Driver File | | Average |
| .pk2 | Silkroad Online Game Data File | | Average |
| .pol | Windows Policy File | | Average |
| .ppd | PostScript Printer Description File | | Average |
| .prefpane | Mac OS X System Preference Pane | | Average |
| .prf | Windows System File | | Common |
| .profile | Bash Shell Profile | | Common |
| .prt | Printer Driver File | | Rare |
| .pwl | Windows Password List | | Average |
| .qvm | Q Virtual Machine | | Rare |
| .rco | PlayStation Portable Resource File | | Uncommon |
| .reg | Registry File | | Average |
| .rfw | Rockchip Firmware File | | Average |
| .rmt | Router Firmware File | | Average |
| .ruf | Samsung DVD and Blu-ray Player Firmware File | | Rare |
| .savedsearch | Spotlight Saved Search | | Average |
| .saver | Mac OS X Screen Saver | | Average |
| .scf | Windows Explorer Command | | Common |
| .scr | Windows Screensaver | | Average |
| .sdb | Custom Application Compatibility Database | | Uncommon |
| .str | Windows Screensaver File | | Rare |
| .swp | Swap File | | Average |
| .sys | Windows System File | | Very Common |
| .sys | Motorola Driver File | | Average |
| .theme | Microsoft Plus! Desktop Theme | | Average |
| .vga | VGA Display Driver | | Average |
| .vgd | Generic CADD VGA Driver | | Average |
| .vxd | Virtual Device Driver | | Average |
| .wdf | Windows Driver Foundation File | | Average |
| .wdgt | Dashboard Widget | | Average |
| .wer | Windows Error Report | | Uncommon |
| .wpx | Printer Description File | | Average |
| .xrm-ms | Microsoft Security Certificate | | Uncommon |