File extensions beginning with the letter A. Commonly used extensions are listed in bold.

	A  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z .a Static Library (more info) .a00 ALZip Second Split Archive File (more info) .a01 ALZip Third Split Archive File (more info) .a02 ALZip Fourth Split Archive File (more info) .a2m AdLib Tracker 2 File (more info) .a2m TS-AudioToMIDI Settings File (more info) .a2w Alice World (more info) .a3l Authorware 3 Library (more info) .a3m Authorware 3 Macintosh File (more info) .a3w Authorware 3 Windows File (more info) .a4l Authorware 4 Library (more info) .a4m Authorware 4 Macintosh File (more info) .a4w Authorware 4 Windows File (more info) .a5l Authorware 5 Library (more info) .a5w Authorware 5 Windows File (more info) .a65 Authorware 6.5 File (more info) .a6p Authorware 6 Program (more info) .aa Generic CD Image (more info) .aa Audible Audio Book File (more info) .aa3 ATRAC Audio File (more info) .aac Advanced Audio Coding File (more info) .aawdef Ad-Aware Definitions File (more info) .aax Audible Enhanced Audiobook File (more info) .ab Applix Builder File (more info) .ab DNA Sequence File (more info) .ab1 DNA Electropherogram File (more info) .ab3 PhotoImpact 3 Album File (more info) .abbu Address Book Backup (more info) .abc ABC Source File (more info) .abc ABC Music Notation (more info) .abcd AudioVisual Book Data File (more info) .abf Adobe Binary Screen Font File (more info) .abi DNA Chromatogram File (more info) .abk Need for Speed Underground Audio (more info) .abk Automatic Backup (more info) .abm Photo Album (more info) .abm Music Album (more info) .abp AVS Barcode Profile (more info) .abr Adobe Photoshop Brushes File (more info) .abw AbiWord Document (more info) .ac Autoconf Script (more info) .ac$ AutoCAD Temporary File (more info) .ac3 Audio Codec 3 File (more info) .ac5 ArtCut 5 Document (more info) .ac6 ArtCut 6 Document (more info) .aca Agent Character Animation File (more info) .acb AOL Cab Launcher (more info) .acc Graphics Accounts Data File (more info) .accdb Access 2007 Database File (more info) .acd ACID Project File (more info) .acd RSLogix 5000 Program (more info) .ace WinAce Compressed File (more info) .acf Agent Character Data File (more info) .acfm Adobe Composite Font Metrics File (more info) .acg Agent Preview File (more info) .acl AutoCorrect List File (more info) .acr ACRobot Script (more info) .acr American College of Radiology Format (more info) .acr Acer eRecovery Management Backup File (more info) .acrodata Acrobat Data File (more info) .acs Agent Character File (more info) .act ADPCM Compressed Audio File (more info) .act Genesis3D Actor File (more info) .act FoxPro Documenting Wizard Action Diagram (more info) .action Automator Action (more info) .acx Atari ST Program (more info) .ad After Dark Screensaver (more info) .ada Ada Source Code (more info) .adb Ada Body File (more info) .adc Scanstudio 16 Color Image (more info) .add Dynamics AX Developer Documentation File (more info) .ade Access Project Extension (more info) .adf Amiga Disk File (more info) .adg Ableton Device Group (more info) .adi Dynamics AX Developer Documentation Index File (more info) .adi AutoCAD Device-Independent Binary Plotter File (more info) .adm Portfolio Admin-Level Access Flag (more info) .adm Administrative Template File (more info) .adp Access Project (more info) .adr Opera Bookmarks File (more info) .ads Ada Specification File (more info) .adt AutoCAD Audit Log (more info) .adt ACT! Document Template (more info) .adx Approach Index File (more info) .adz Compressed Amiga Disk File (more info) .aea Ae Timer Alarm Document (more info) .aep Activ E-Book Project (more info) .aep After Effects Project (more info) .afm Adobe Font Metrics File (more info) .afp FileProtector Encrypted File (more info) .afp Advanced Function Presentation File (more info) .afploc Apple Filing Protocol Location (more info) .aft Ancestry.com Family Tree Database (more info) .agi Asterisk Gateway Interface File (more info) .agif Active GIF Creator Project (more info) .agp ArtGem Project File (more info) .ahd Dynamics AX Online Help Data File (more info) .ahi Dynamics AX Online Help Index File (more info) .ahk AutoHotkey Script (more info) .ahl eMule Metadata File (more info) .ahs Adobe Halftone Screen File (more info) .ahx WinAHX Tracker Module (more info) .ai Adobe Illustrator File (more info) .aic Advanced Image Coding File (more info) .aif Audio Interchange File Format (more info) .aif Symbian Application Information File (more info) .aifb AIF Builder Project File (more info) .aifc Compressed Audio Interchange File (more info) .aiff Audio Interchange File Format (more info) .aim AOL Instant Messenger Launch File (more info) .aim AIMMS ASCII Model File (more info) .ain AIN Compressed File Archive (more info) .aip Illustrator Plug-in (more info) .air Adobe AIR Installation Package (more info) .ais Velvet Studio Instrument (more info) .ais ACDSee Image Sequence (more info) .ajp CCTV Video File (more info) .akp Akai Sampler File (more info) .al A-Law Compressed Sound Format (more info) .alaw A-Law Compressed Sound Format (more info) .alc Dynamics AX Label Description File (more info) .ald Dynamics AX Application Label Data File (more info) .ali Dynamics AX Label Index File (more info) .all Cubasis Project File (more info) .alt Dynamics AX Temporary File (more info) .alz ALZip Archive (more info) .am4 AutoPlay Media Studio 4 Project File (more info) .am5 AutoPlay Media Studio 5 Project File (more info) .am6 AutoPlay Media Studio 6 Project (more info) .am7 AutoPlay Media Studio 7 Project (more info) .amb AIMMS Model File (more info) .amf Advanced Module File (more info) .amfm Adobe Multiple Font Metrics File (more info) .amr Adaptive Multi-Rate Codec File (more info) .ams Extreme Tracker Module (more info) .ams Velvet Studio Module (more info) .ams Adobe Monitor Setup file (more info) .amu Sony Photo Album (more info) .amv Anime Music Video File (more info) .amx AMX Mod Plugin File (more info) .amx Adobe Motion Exchange File (more info) .amxx AMX Mod X Plugin File (more info) .an1 Street Atlas USA Draw File (more info) .an8 Anim8or File (more info) .ani Windows Animated Cursor (more info) .anm 3D Animation File (more info) .anme Anime Studio Project (more info) .ann Help Annotations (more info) .ans ANSI Text File (more info) .aob DVD-Audio Audio Object File (more info) .aod Dynamics AX Object Data File (more info) .aoi Dynamics AX Application Object Index File (more info) .aol America Online File (more info) .ap Active Page (more info) .apa RSView Development Project Archive (more info) .ape AVS Plugin Effects File (more info) .ape Monkey's Audio Lossless Audio File (more info) .api Acrobat Plug-in (more info) .apk Android Package File (more info) .apng Animated Portable Network Graphic (more info) .app Symbian OS Application (more info) .app Mac OS X Application (more info) .app FoxPro Generated Application (more info) .applescript AppleScript File (more info) .apr ArcView Project File (more info) .apz Autoplay Media Studio Exported Project (more info) .ar Unix Static Library (more info) .arc Compressed File Archive (more info) .arc African Safari Data File (more info) .arch00 F.E.A.R. Game Archive (more info) .ard ArtiosCAD Workspace File (more info) .arf WebEx Advanced Recording File (more info) .ari ARI Compressed File Archive (more info) .arj ARJ Compressed File Archive (more info) .ark PowerDesk Pro Archive (more info) .aro SteelArrow Web Application File (more info) .arp Advanced RAR Password Recovery Setup (more info) .arr Amber Graphic File (more info) .arr Advanced RAR Password Recovery Project (more info) .art Art Document (more info) .art Artifacts Artifact File (more info) .art AOL Compressed Image File (more info) .artproj Artifacts Project (more info) .as ActionScript File (more info) .asa ASP Configuration File (more info) .asat Assemble SAT 3D Model File (more info) .asc ASCII Text File (more info) .asc Autodesk ASCII Export File (more info) .ascii ASCII Text File (more info) .ascx Active Server Custom Control (more info) .ase Autodesk ASCII Scene Export File (more info) .ase Velvet Studio Sample (more info) .asf Advanced Systems Format File (more info) .ashx ASP.NET Web Handler File (more info) .ask askSam Database (more info) .asl Photoshop Style (more info) .asm Assembly Language Source Code File (more info) .asm Solid Edge Assembly Document (more info) .asmx Active Server Method File (more info) .asp Active Server Page (more info) .aspx Active Server Page Extended (more info) .asr ActionScript Remote Document (more info) .ast ClarisWorks Assistant File (more info) .ast Adobe Color Separations Table (more info) .asx Microsoft ASF Redirector File (more info) .atf Photoshop Transfer Function File (more info) .atn Photoshop Actions File (more info) .atom Atom Syndication Format (more info) .atr Atari Disk Image (more info) .atrac Sony ATRAC Audio File (more info) .atx Animation Master Plugin File (more info) .aty Association Type Placeholder (more info) .atz Atomic Time Zone File (more info) .atz Aston Compiled Theme (more info) .au Audio File (more info) .au3 AutoIt v3 Script (more info) .aud Video Game Compressed Audio File (more info) .aup Audacity Project File (more info) .avb Avid Bin File (more info) .avi Audio Video Interleave File (more info) .avl ArcView Legend File (more info) .avr Audio Visual Research File (more info) .avs Application Visualization System File (more info) .avs AVS Preset File (more info) .avs AviSynth Script File (more info) .awb AMR-WB Audio File (more info) .awc Emulex AWC Firmware Update File (more info) .awd Artweaver Document (more info) .awd FaxView Document (more info) .awd Award BIOS Update File (more info) .awg Activeworlds Object Group File (more info) .awk AWK Script (more info) .ax DirectShow Filter (more info) .axm AXMEDIS Object (more info) .axx AxCrypt Encrypted File (more info) .azw Amazon Kindle eBook File (more info)

All File Extensions | "A" Computer Terms

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