| Extension | Information |
| A | ADA Program |
| A | Assembly Source Code (Macintosh) |
| A | UNIX Library |
| A | Free Pascal Archive File for Linux or DOS Version (FPC Development Team) |
| A00 | Archive Section |
| A01 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A01 | ARJ Multi-volume Compressed Archive (can be 01 to 99) (also see .000) |
| A01 | Archive Section |
| A02 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A02 | Archive Section |
| A03 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A03 | Archive Section |
| A03 | annotare ava 04 Project File (annotare.net) |
| A04 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A04 | Archive Section |
| A05 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A05 | Archive Section |
| A06 | Lotto Pro 2002 Smart Number Ticket |
| A06 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A06 | Archive Section |
| A07 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A07 | Archive Section |
| A08 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A08 | Archive Section |
| A09 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A09 | Archive Section |
| A1 | Free Pascal Archive File for GO321v1 Platform (FPC Development Team) |
| A10 | OzWin CompuServe E-mail/Forum Access SYSOP File |
| A11 | AOL Instant Messenger Graphic (America Online, Inc.) |
| A21 | Soundweb Firmware File (BSS Audio) |
| A2A | APLASCII EISPACK |
| A2A | IBM Voice Type Language Vocabels File |
| A2A | Sharp APL Workspace Export File |
| A2B | A2B Player Playlist (DigitalPhono.com) |
| A2M | AudioToMidi Settings |
| A2M | AdLib Tracker 2 |
| A3 | Unrelated Inventions Audiotools Show Log |
| A31 | Authorware Ver. 3.x Library |
| A3D | Amapi 3D Modeling (Eovia) |
| A3K | Yamaha A3000 Sampler File |
| A3L | Authorware Ver. 3.x Library |
| A3M | Unpackaged Authorware MacIntosh File |
| A3W | Unpackaged Authorware Windows File |
| A41 | Authorware Ver. 4.x Library |
| A4L | Authorware Ver. 4.x Library |
| A4M | Unpackaged Authorware MacIntosh File |
| A4P | Authorware File Without Runtime |
| A4W | Unpackaged Authorware Windows File |
| A51 | Authorware Ver. 5.x Library |
| A52 | Atari 5200 Game Image |
| A5L | Authorware Ver. 5.x Library |
| A5W | Unpackaged Authorware Windows File |
| A5W | Alpha Five Web Publishing Page (Alpha Software, Inc.) |
| A60 | Roland Garros Tennis MVTS File |
| A64 | Artist 64 |
| A65 | Macromedia Authorware v6.5 |
| A6P | Authorware Application (Macromedia, Inc.) |
| A78 | Atari 7800 ROM Image |
| A8 | Cubicomp PictureMaker 24bit 3D Animation |
| A86 | A86 Assembler Source Code |
| AA | Audio Book |
| AA | PROGNOSIS Automated Analyst Document File |
| AAA | App Cam Automation |
| AAA | Softphrase Automation File |
| AAA | Sybase SQLAnywhere Temp File |
| AAA | Xtal Backup |
| AAB | Authorware Binary (Macromedia) |
| AAC | MPEG-2 Advanced Audio Coding File |
| AAF | Advanced Authoring Format File |
| AAM | Authorware Shocked File (Map) (Macromedia) |
| AAO | America's Army Map |
| AAP | Apollo Advanced Playlist |
| AAPKG | ArchestrA IDE Package (Invensys) |
| AAR | Axis Archive (Apache Software Foundation) |
| AAS | Authorware Shocked Packet (Segment) (Macromedia) |
| AAS | Bong Script File |
| AAS | Movie Clip; Autodesk Animation Setup; used by Compton's Reference Collection |
| AAS | Star Trek Elite Force Bot Support File (Raven Software) |
| AAS | Audible Words File (Audible, Inc.) |
| AAT | Arcinfo Line Data Attribute Data |
| AATREND | ActiveFactory Trend File (Invensys Systems, Inc.) |
| AB | Applix Builder |
| AB$ | AutoCAD Spooled Plot (Autodesk, Inc.) |
| AB1 | Chromas Lite Nucleotide Sequence Analysis Results (Technelysium Pty Ltd) |
| AB2 | Parson's Address Book |
| AB3 | PhotoImpact Album File |
| AB4 | ENIAC Computing AB4 Accounting & Business File |
| AB6 | AB Stat Data |
| AB8 | AB Stat Data |
| ABA | Palm Address Book File (Palm) |
| ABAP | ABAP Source Code (SAP AG) |
| ABC | ABC Programming Language |
| ABC | Athena 16 Address Book |
| ABC | FlowCharter Data File (iGrafx (a division of Corel Inc.)) |
| ABC | Musical Notation Language File |
| ABC | Pro-Act |
| ABC | ACT! E-mail Address Book File (Best Software CRM Division) |
| ABC | LithTech Game 3D Model (Touchdown Entertainment, Inc.) |
| ABD | Adventure Builder Database |
| ABD | AmBiz Bonus Calculator Data File |
| ABD | The Bat! Address Book (RITLABS) |
| ABF | Binary Screen Font (Adobe) |
| ABG | Fifa World Cup Game Data File |
| ABI | ABI- CODER (ABI- Software Development) |
| ABI | AOL 6 Organizer (America Online, Inc.) |
| ABI | dnaLIMS ABI Trace File (dnaTools) |
| ABI | Chromas Nucleotide Sequence Analysis Results (Technelysium Pty Ltd) |
| ABK | AMOS Basic Data (SPSS Inc.) |
| ABK | Any Automatic Backup |
| ABK | Corel Draw AutoBackup |
| ABK | HP-95LX Appointment Book File |
| ABK | Ability Office Write Document Backup (Ability Software) |
| ABK | Need for Speed: Underground Audio File (Electronic Arts, Inc.) |
| ABK | AMOS Music Bank |
| ABL | Maxagrid Avails Data File |
| ABL | Xilinx Integrated Software Environment ABEL Hardware Description Language (Xilinx, Inc.) |
| ABM | Album |
| ABM | HitPlayer Audio Album File |
| ABM | Photo Impressions Album (ArcSoft, Inc.) |
| ABO | Applix Builder Turbo |
| ABR | Photoshop Brush (Adobe) |
| ABS | Abscissa Data File |
| ABS | Abstracts |
| ABS | MPEG Audio Sound File |
| ABS | Optocat |
| ABS | PC GNU Compiler Output |
| ABS | Absolute Packager Configuration File (Xceed Software Inc.) |
| ABS | AB SuDoKu Sudoku Save Game (Andrei Baronov) |
| ABS | Absolute Database Database (ComponentAce) |
| ABT | The Arbiter Sports Official Schedule |
| ABU | ACT! E-mail Address Book File (Best Software CRM Division) |
| ABW | AbiWord Document File (The AbiSource Community) |
| ABX | WordPerfect Address Book File (Corel Corporation) |
| ABY | AOL (America Online, Inc.) |
| ABZ | AbszOrb |
| AC | CaseWare Working Papers Client File |
| AC | AC3D Geometry File (Inivis) |
| AC$ | AutoCAD Undo Info (Autodesk, Inc.) |
| AC1 | Weaver Spider Software (Weaver Spider Software) |
| AC3 | AC3 Audio File Format |
| ACA | Agent Character (Microsoft) |
| ACA | Project Manager Workbench File |
| ACAD | AutoCAD Database (Autodesk, Inc.) |
| ACB | ACMB Graphic Image |
| ACB | AOL Cab Launcher (America Online, Inc.) |
| ACB | Photoshop Color Book (Adobe) |
| ACC | Atari ST Executable |
| ACC | Composer File (Microsoft) |
| ACC | DR-DOS Viewmax File |
| ACC | Graphic Accounts Accounts Data (FKJ Software) |
| ACCESS | Java Access Control File (Sun) |
| ACD | Agent Character Definition (Microsoft) |
| ACD | ALAN Game |
| ACD | allCLEAR Flowcharting File |
| ACD | Chromeleon Channel Raw Data |
| ACD | Nascar Racing 2002 Arcade Car Setup (Sierra) |
| ACD | Sonic Foundry Acid Music File (Sony) |
| ACD | RSLogix 5000 Project File (Rockwell Automation) |
| ACE | Aces200 |
| ACE | WinAce Compressed File (e-merge GmbH) |
| ACE | Casting Electronic Enterprise CV Archive (Casting Electronic) |
| ACE | Jupiter Ace Snapshot |
| ACE | Train Simulator Texture File (Microsoft Corporation) |
| ACF | Agent Character (Microsoft) |
| ACF | DB/TextWorks Database Access Control File |
| ACF | Photoshop Custom Filter (Adobe) |
| ACF | X-Plane Plane Description File (Laminar Research) |
| ACF | AdviceCalculator (JRK Software) |
| ACF | Spectramap Application Colors File (Coloritto BV) |
| ACG | Agent Preview (Microsoft) |
| ACG | Age of Wonders Saved Game (Triumph Studios) |
| ACGD | ACG Case-Mix System ACG Predictive Model (Johns Hopkins University) |
| ACGI | AppleSearch CGI Interface |
| ACGL | ACG Case-Mix System License File (Johns Hopkins University) |
| ACH | Rockwell Software Logix 5 File |
| ACH | Speccy Snapshot |
| ACH | Medlin Accounting Automated Clearing House File (Medlin Accounting) |
| ACI | ACI Development Appraisal |
| ACL | Access Control List (Microsoft) |
| ACL | ACL For Windows |
| ACL | Corel Draw 6 Keyboard Accelerator |
| ACL | Office AutoCorrect List (Microsoft) |
| ACL | RaidenFTPD Rights File |
| ACM | ACBM Image File |
| ACM | Audio Compression Manager Driver (Microsoft) |
| ACM | Infinity Game Engine Sound (BioWare Corp.) |
| ACM | Interplay Compressed Sound File |
| ACM | Movie File in some games |
| ACM | Photoshop Command Button (Adobe) |
| ACM | Windows System File |
| ACM | American Civil War File (Interactive Magic) |
| ACMB | Graphics File |
| ACMD | Apache Commander Project (Zecos Software) |
| ACO | Photoshop Color Swatch File (Adobe) |
| ACO | Fast-Talk Acoustic Model File (Fast-Talk Communications, Inc.) |
| ACO | ArCon Project (TRIXL GmbH) |
| ACP | ACB Compressed File Archive |
| ACP | Acrobat Paper Capture Temporary File (Adobe) |
| ACP | Office Assistant Preview File (Microsoft) |
| ACP | Action! Document (Macromedia) |
| ACQ | AcqURL |
| ACR | American College of Radiology |
| ACR | Dicom |
| ACR | Medlin Accounting Accrual Method Adjustments (Unpaid Invoices) (Medlin Accounting) |
| ACS | Agent Character (Microsoft Corporation) |
| ACT | Action! Presentation (Macromedia) |
| ACT | Animation:Master Action (Hash) |
| ACT | DataWave Physiological Data File |
| ACT | FoxPro Documenting Wizard Action Diagram (Microsoft) |
| ACT | Office Actor Program File (Microsoft) |
| ACT | Photoshop Color Table (Adobe) |
| ACT | ADPCM Compressed File Recorded by Some MP3 Players/Voice Recorders |
| ACT | Train Simulator Activity File (Microsoft Corporation) |
| ACTIONS | Photoline4 Defaults File |
| ACTPROJ | Visual Studio .NET ACT Project (Microsoft) |
| ACU | AppleLink-PE Compression Format |
| ACU | ACUCOBOL-GT Intermediate Object File (Acucorp, Inc.) |
| ACV | OS/2 Audio Drivers |
| ACV | Photoshop Saved Curve (Adobe) |
| ACW | Accessibility Wizard Settings (Microsoft) |
| ACW | American Civil War Game Save File (Interactive Magic) |
| ACW | AutoCaption Worksheet File (Image Logic Corporation) |
| ACX | Atari ST Executable |
| ACX | FOCUS/WebFOCUS File Description |
| ACX | Rational XDE (IBM) |
| AC_ | CaseWare Working Papers Compressed Client File |
| AC_ | Creativ compressed Sb16 sbide file |
| AD | After Dark Screen Saver |
| AD | Ascend Password Protocol |
| AD | AxSys Script File (Genomic Solutions) |
| AD | AppleDouble Encoded File (Apple Computer, Inc.) |
| AD! | OzWin CompuServe E-mail/Forum Access QS-Special - Get Marked Online |
| AD2 | Compressed Voice File |
| AD3 | Compressed Voice File |
| ADA | ActiveDocs Answer Set |
| ADA | ADA Program |
| ADA | Advanced Digital Audio Compressed Audio |
| ADB | ADA Package Body |
| ADB | ALLDATA |
| ADB | HP 100LX Organizer Appointment Database |
| ADB | LICOM AlphaCAM Diecut VB Macro |
| ADB | ACT! Activity Data File (Best Software CRM Division) |
| ADB | Alpha Five Database Information File (Alpha Software, Inc.) |
| ADB | Advanced Integrated Maintenance Support System (AIMSS) Runtime Project Configuration File (Raytheon Company) |
| ADBA | Advanced Integrated Maintenance Support System (AIMSS) Author Project Configuration File (Raytheon Company) |
| ADBLOCK | Alpha Five Temporary Locking File (Alpha Software, Inc.) |
| ADC | ActiveDocs Clipping Catalog |
| ADC | ADC Data Acquistion |
| ADC | Chromeleon Demo Data File |
| ADC | Lingvo Dictionary Text File |
| ADC | Scanstudio 16-color Bitmap Graphic File |
| ADC | TI/MIT ADC Format Sound |
| ADC | ClearSight Analyzer Trace File (ClearSight Networks, Inc.) |
| ADC | XMap ImageReg Output File (Delorme) |
| ADD | Advantage Database Server Data Dictionary |
| ADD | LICOM AlphaCAM Diecut Drawing |
| ADD | OS/2 Adapter Device Driver |
| ADD | PageMaker (Adobe) |
| ADE | Access Project Extension (Microsoft) |
| ADE | ADC Audio File |
| ADEX | ADEX Corporation ChromaGraph Graphics Card Bitmap Graphic |
| ADF | Actual Drawing File |
| ADF | Adapter Description File |
| ADF | Admin Config File |
| ADF | Amiga Disk File (Amiga) |
| ADF | ArcView ARC/INFO Coverage Data File (ESRI) |
| ADF | Dog Creek QC Mask File |
| ADF | MicroSim PCBoard Photoplot Aperture Definition File |
| ADF | ReliaSoft ALTA 1 |
| ADF | Wyatt Technology ASTRA(r)Chromatography |
| ADF | I-DEAS Associated Data File (EDS) |
| ADF | Grand Theft Auto Vice City Radio Station (Take-Two Interactive Software, Inc.) |
| ADI | Advantage Data Server Database Index File |
| ADI | AutoCAD Plotter File (Autodesk, Inc.) |
| ADJ | LISCAD Plus Adjustment File |
| ADL | OzWin CompuServe E-mail/Forum Access QS-Special Get Marked |
| ADL | QEMM MCA Adapter Description Library |
| ADL | DESQview (Symantec) |
| ADM | Addict Compiled Dictionary |
| ADM | Advantage Data Server Database Memo File |
| ADM | After Dark Screen Saver Module |
| ADM | LICOM AlphaCAM Diecut Parameter Macro |
| ADM | SCSI Driver |
| ADM | Windows Policy Template (Microsoft) |
| ADM | Portfolio Admin-level Acces Flag (Extensis, Inc.) |
| ADN | Access Blank Project Template (Microsoft) |
| ADN | 1-2-3 Add-in Utility (IBM) |
| ADO | Photoshop Duotone Options (Adobe) |
| ADO | Stata Program |
| ADOBENET | Studio Snapshot Tool Application (Adobe) |
| ADOC | Authentica Secure Office Protected Word Document (Authentica) |
| ADOS | ADOS Compound Document (ADOS Corporation) |
| ADP | Access Project (Microsoft) |
| ADP | AOL Server Dynamic Page (America Online, Inc.) |
| ADP | Astound Dynamite |
| ADP | FaxWorks Modem Setup File |
| ADP | LICOM AlphaCAM Diecut Post |
| ADPCM | Intel/DVI Adaptive Differential Pulse Code Modulation Format Sound |
| ADR | Address Book |
| ADR | Address Plus Database |
| ADR | After Dark Random Screen Saver Module |
| ADR | Opera Web Browser Bookmark File (Hotlist) (Opera Software ASA) |
| ADR | Smart Address Address Book |
| ADR | XAIRON-Addy Address Manager Data File |
| ADS | ADA Package Specification |
| ADS | ADS Applications File (Autodesk, Inc.) |
| ADT | AdTech Fax |
| ADT | Advantage Data Server Database File |
| ADT | AutoCAD Audit Report (Autodesk, Inc.) |
| ADT | Casio Travel Phrase Database |
| ADT | HP NewWave Card Application Data File |
| ADT | LICOM AlphaCAM Diecut Tools |
| ADT | Lingvo Dictionary File |
| ADT | ACT! Document Template (Best Software CRM Division) |
| ADT | MediSoft Database Dictionary File |
| ADV | GUS Virtual Device Driver |
| ADV | TAPCIS Advanced Commands (User Entered) |
| ADW | ADHAWIN Multilingual Transliteration Scheme |
| ADX | Archetype Designer Document |
| ADX | Dynazip Active Delivery Script |
| ADX | Approach Index File (IBM) |
| ADX | Dreamcast Audio File (Sega) |
| ADZ | Amiga GZ-Packed Disk Image (Amiga) |
| AE | SoftQuad Author/Editor File |
| AEB | LICOM AlphaCAM Wire EDM VB Macro |
| AEC | DataCAD Double Precision Drawing (DATACAD LLC) |
| AED | LICOM AlphaCAM Wire EDM Drawing |
| AEF | ELECTRICAL Designer |
| AEG | Netmino File |
| AEH | iPer Advanced Embedded Hypertext (Visual Vision) |
| AEM | LICOM AlphaCAM Wire EDM Parameter Macro |
| AEP | ArcExplorer Project (Environmental Systems Research Institute, Inc. (ESRI)) |
| AEP | LICOM AlphaCAM Wire EDM Post |
| AEP | After Effects Project File (Adobe) |
| AER | Atmosphere File (Adobe) |
| AES | After Effects Stablilzer Settings (Adobe) |
| AET | After Effects Tracker Settings (Adobe) |
| AEU | AutoRoute Express Europe Route (Microsoft) |
| AEX | Alpha Five Compiled Add-in Library Script (Alpha Software, Inc.) |
| AEX | Art Explosion Greeting Card Factory Deluxe Graphic (Nova Development Corporation) |
| AEX | Pretty Good Privacy (PGP) Armored Extracted Public Encryption Key (PGP Corporation) |
| AEXPK | Pretty Good Privacy (PGP) Armored Extracted Public Key (PGP Corporation) |
| AF | 3DPlus2 Model (Serif) |
| AF2 | ABC Flowchart |
| AF3 | FlowCharter Ver. 3 & 4 (iGrafx (a division of Corel Inc.)) |
| AFB | LICOM AlphaCAM Flame VB Macro |
| AFC | Apple Sound (Apple Computer, Inc.) |
| AFC | ArisFlow Commander |
| AFD | ArisFlow Diagram |
| AFD | LICOM AlphaCAM Flame Drawing |
| AFD | Prismo Graphics ActiveFile Data |
| AFF | AnyForm Form |
| AFG | Guitar Musik Trainer File |
| AFI | Truevision Bitmap Graphic |
| AFL | AnimaFlex RubberFlex Animation |
| AFL | Lotus Font (IBM) |
| AFL | X-Plane Airfoil (Laminar Research) |
| AFL | XMap (Delorme) |
| AFM | HP NewWave Cardfile Application |
| AFM | LICOM AlphaCAM Flame Parameter Macro |
| AFM | LOUT File |
| AFM | Outline Font Metric (Adobe) |
| AFM | Abassis Finance Manager Data File (SmartMedia Informatica) |
| AFM | DESQview (Symantec) |
| AFM | FormMaster Editor Form Template (AT SYSTEMS S.R.L.) |
| AFP | Flowchart Symbol Palette |
| AFP | Gangsters Game File |
| AFP | IBM Transactional Data Format (Advanced Function Print) |
| AFP | LICOM AlphaCAM Flame Post |
| AFP | Papyrus Document Storage Format |
| AFP | Prismo Graphics ActiveFile Proxy |
| AFP | XMap Flight Plan or Flight Plan Statistic File (Delorme) |
| AFS | Filter Factory Photoshop Filter |
| AFS | Sega Dreamcast Compressed Audio |
| AFS | Type Manager Font Set (Adobe) |
| AFT | AnyForm Template |
| AFT | Flowchart Template |
| AFT | Ancestry Family Tree Data File (MyFamily.com Inc.) |
| AFW | Flowchart Work Area |
| AFW | Industrial Aspect Integrator Platform (ABB Ltd) |
| AFX | Auto FX Photographic Edges (Auto FX Software) |
| AFZ | Ancestry Family Tree Backup Data File (MyFamily.com Inc.) |
| AG | Applix Graphic |
| AG | Argus Spreadsheet |
| AG | Agenda Application (IBM) |
| AG4 | Access G4 File (Microsoft) |
| AGC | AfterGRASP Compiled Script (John Bridges) |
| AGF | Atlas GeoFile |
| AGG | Graphic |
| AGM | DOTAGM.JAR Packed Audio File (agm digital arts GmbH) |
| AGN | Psion Series 3 Agenda (Psion PLC) |
| AGO | Autolog Script (Soft Machines) |
| AGP | Aspen Graphics Pages |
| AGP | AppGini MySQL Code Generator Project (BigProf Software) |
| AGR | APM Graph Vector Graphic (APM) |
| AGR | Aepryus Graph Image or Screen Saver File (Aepryus Software) |
| AGS | AfterGRASP Script (John Bridges) |
| AGS | AppGini Saved Style Sheet (BigProf Software) |
| AGT | PeerAgent Typed Executable E-mail |
| AGW | Aspen Graphics Windows |
| AGX | Rational XDE (IBM) |
| AHB | AIM High Briefcase Report File (Cosby Clifton Computer Consultants Ltd) |
| AHD | Asus Probe |
| AHF | ASP Header |
| AHK | AutoHotkey Script (AutoHotkey) |
| AHP | AutoCAD Help (Autodesk, Inc.) |
| AHQ | AudioHQ Plug-in Module |
| AHS | Photoshop Halftone Screens (Adobe) |
| AHTM | HTML File |
| AHTML | HTML File |
| AHX | WinAHX THX Tracker Music (Abyss) |
| AI | Advantage Database Server |
| AI | Corel Trace Drawing |
| AI | EARS Component File |
| AI | Illustrator Vector Graphic (Adobe) |
| AI | Progress Database After Image File (Progress Software) |
| AI | Ai Archiver Archive |
| AI | Rise of Nations AI File (Microsoft) |
| AI3 | Generic Encapsulated PostScript Graphic Format |
| AI4 | Generic Encapsulated PostScript Graphic Format |
| AI5 | Generic Encapsulated PostScript Graphic Format |
| AI6 | Generic Encapsulated PostScript Graphic Format |
| AI7 | Generic Encapsulated PostScript Graphic Format |
| AIC | Advanced Image Coding Bitmap |
| AIF | Audio Interchange File |
| AIF | Knowledgeware Setup Information |
| AIF | SymbianOS Application Information File |
| AIF | OS/2 Program Information File (IBM) |
| AIFC | Audio Interchange File |
| AIFF | Audio Interchange File |
| AIH | ArcView Optional Index File (ESRI) |
| AIJ | Oracle After-Image Journal |
| AIL | AutoImager |
| AIM | Asm Text Mode Image File (The Ultimate Draw) |
| AIM | AOL Instant Messenger (America Online, Inc.) |
| AIML | Artificial Intelligence Markup Language |
| AIN | AIN Compressed Archive |
| AIN | ArcView Optional Index File (ESRI) |
| AINSO | VAX CRYSTALS Chemical Crystallogaphy File |
| AIO | APL File Transfer Format |
| AIP | Audiosoft Parameter File |
| AIP | Illustrator Plug-in (Adobe) |
| AIP | Star Trek Armada Arficicial Intelligence Parameters |
| AIQ | AzureIQ Client |
| AIR | Align It! Resource |
| AIR | Automatic Image Registration |
| AIR | Flight Simulator Aircraft Performance Info File (Microsoft) |
| AIR | SeeYou Airspace (Naviter) |
| AIRPORT | RealFlight Radio Control Flying Site (Knife Edge Software) |
| AIS | ACDSee Image Sequence File (ACD Systems Ltd.) |
| AIS | Array of Intensity Samples |
| AIS | Velvet Studio Instruments |
| AIW | Formula 1 car race 2001 Season01 School France file |
| AIX | HP NewWave Cardfile Application Data |
| AJA | AJC Active Backup Backup Revision Control Archive (AJC Software) |
| AJB | LICOM AlphaCAM Water Jet VB Macro |
| AJD | LICOM AlphaCAM Water Jet Drawing |
| AJG | AJC Grep Project File (AJC Software) |
| AJL | ARCserve Backup Journal File (Computer Associates) |
| AJM | LICOM AlphaCAM Water Jet Parameter Macro |
| AJP | LICOM AlphaCAM Water Jet Post |
| AJP | Anfy Applet Generator Saved File (Anfy Team) |
| AJZ | Jukebox MP3 Player Firmware Update (Archos) |
| AK | Audio Utility Tuningwrench Compressed File |
| AKF | Acrobat Key File (Adobe) |
| AKM | Aksharamala Binary Keymap File (Deshweb.com Pvt. Ltd.) |
| AKS | Aksharamala Ver 2.0 Binary Keymap File (Deshweb.com Pvt. Ltd.) |
| AKT | Aksharamala Source Keymap File (Deshweb.com Pvt. Ltd.) |
| AKW | RoboHELP Help Project Index File |
| AL | ALAW Format Sound |
| AL | Oracle File |
| AL$ | Cubase Compressed File (Steinberg) |
| ALA | Alan Adventure Language File |
| ALA | Sharp Fax File |
| ALARMZ | Alarmz Alarm File (Fichier d'alarmes) (Francis Gagn) |
| ALAW | ALAW Format Sound |
| ALB | Image Commander Album (Corel Corporation) |
| ALB | LICOM AlphaCAM Laser VB Macro |
| ALB | Photo Soap2 File |
| ALB | Cubase or VST Backup Song File (Steinberg) |
| ALB | Pro/DESKTOP Album (PTC) |
| ALB | Raduga Playlist (WoLoSoft) |
| ALB | Alpha Five Data Dictionary (Alpha Software, Inc.) |
| ALB | Chief Architect Library File (Chief Architect) |
| ALB | Web Easy Album (VCOM/Avanquest Publishing USA, Inc.) |
| ALBM | Photosmart Photo Printing Album (Hewlett-Packard Development Company, L.P.) |
| ALBM | webAlbum Photo Album (Goopers - Logan Mueller) |
| ALC | MP3 Embedded Dynamic Lyrics |
| ALC | Norton Internet Security Ad Server File |
| ALC | ACUCOBOL-GT License File (Acucorp, Inc.) |
| ALD | LICOM AlphaCAM Laser Drawing |
| ALD | Aladdin Interactive DSP Document (Hitech Development AB) |
| ALE | Avid Log Exchange |
| ALF | Abacus Law (Abacus Data Systems, Inc.) |
| ALF | ACT! User Logon Tracking (Best Software CRM Division) |
| ALF | AdventNet Look and Feel Standards |
| ALF | Airpro 2000 Landfile |
| ALF | ALF Logic |
| ALF | Aventail Connect License |
| ALF | Cadence Ambit BuildGates |
| ALF | Color Quick Label |
| ALF | LANDesk Client Manager Configuration File |
| ALF | VPCom Remote User Configuration File |
| ALG | ARCSOLO Activity Log |
| ALG | Netmino File |
| ALH | Aladdin Interactive DSP Model Header File (Hitech Development AB) |
| ALI | OM2 OMALI Native OMALI Document |
| ALI | SAP Proprietary Format Document File |
| ALI | DESQview (Symantec) |
| ALIAS | Alias Image |
| ALIGN | Insight II Sequence Alignment File (Accelrys Software Inc.) |
| ALL | Arts & Letters Symbols and Characters |
| ALL | FRQView File List of All Files |
| ALL | 1-2-3 Always Working Page Format File (IBM) |
| ALL | Cubase or VST Song File (Steinberg) |
| ALL | WordPerfect Printer Info (Corel Corporation) |
| ALL | OS/2 Program List (IBM) |
| ALM | LICOM AlphaCAM Laser Parameter Macro |
| ALM | Aley's Module v1.0, 1.1, 1.2 |
| ALM | Alpha Five Database Information File (Alpha Software, Inc.) |
| ALM | AL-Mail Mailbox File (AL-Mail) |
| ALN | Grlib Saoimage File |
| ALO | Almanac Support File |
| ALP | LICOM AlphaCAM Laser Post |
| ALPHA | Raw Alpha Bytes Bitmap |
| ALR | VirusScan Alert File (Network Associates) |
| ALR | ADRIFT Language Resource (ADRIFT) |
| ALS | Alias Image |
| ALS | Calmira Shortcut File |
| ALS | Pro/ENGINEER Temporary File (PTC) |
| ALS | Arcade Lines Graphic Resource File (Lobstersoft) |
| ALT | ReliaSoft ALTA 6 |
| ALT | WordPerfect Menu File (Corel Corporation) |
| ALT | Aladdin Interactive DSP Message Text (Hitech Development AB) |
| ALV | Photoshop Levels (Adobe) |
| ALV | Vbox Available Languages File (Aladdin Knowledge Systems) |
| ALX | ActiveX Layout File |
| ALX | OM2 OMALI Plug-in Extension |
| ALX | Alpha Five Library Index (Alpha Software, Inc.) |
| ALZ | ALZip Compressed File (ESTsoft, Corp.) |
| ALZ | Game File |
| AL_ | Audio Utility Juker Compressed File |
| AM | Advantage Database Server |
| AM | Anark Studio Media File (Anark) |
| AM | Applix SHELF Macro |
| AM | Music File |
| AM2 | AutoPlay Menu Studio Ver. 2 (Indigo Rose Software) |
| AM3 | AutoPlay Menu Studio Ver. 3 (Indigo Rose Software) |
| AMA | Fifa2000 Feart File |
| AMAYA | Amaya |
| AMB | LICOM AlphaCAM 3D Mill, 2D Mill VB Macro |
| AMB | Radiance Ambient File Format |
| AMC | Ant Movie Catalog |
| AMC | Wireless Analyzer Captured Data (AirMagnet) |
| AMD | ABBYY Finereader 5.0 Pro File (ABBYY Software House) |
| AMD | LICOM AlphaCAM 3D Mill, 2D Mill Drawing |
| AMD | AMUSIC AdLib Tracker |
| AME | ACT! E-mail System Library (Best Software CRM Division) |
| AMF | Advanced Module Format Music |
| AMF | Amiga Metafile (Amiga) |
| AMF | DSMIA/Asylum Module Music |
| AMF | Autolog Macro (Soft Machines) |
| AMF | ADRIFT Module File (ADRIFT) |
| AMFF | Amiga Metafile (Amiga) |
| AMG | AMG ACTOR System Image |
| AMG | AMGC Compressed Archive |
| AMG | Netmino File |
| AMI | Amiga Paint File (Amiga) |
| AMI | Cocreate SolidDesigner Annotation File |
| AMI | AMI BIOS Firmware Update File (American Megatrends Inc.) |
| AMIGA | Amiga (Amiga) |
| AML | AutoMage |
| AML | SAS Activity-Based Management Model File (SAS Institute, Inc.) |
| AML | Mio Technology Application Markup Language (Mioplanet Technologies, Inc.) |
| AMM | AMM |
| AMM | LICOM AlphaCAM 3D Mill, 2D Mill Parameter Macro |
| AMM | Orchida Knitting System (Orchida Soft) |
| AMM | Microphone Modeler Model File (Antares Audio Technologies) |
| AMODEL | ActiveModeler Professional Project File (KAISHA-Tec Co. Ltd.) |
| AMOS | AMOS Basic Code |
| AMP | Connectivity Memory Model AMPA and NMDA Parameters Input File |
| AMP | LICOM AlphaCAM 3D Mill, 2D Mill Post |
| AMP | Photoshop Arbitrary Map Settings (Adobe) |
| AMP | PlayMedia AMP MP3 Audio File |
| AMR | Adaptive Multi-Rate ACELP Codec |
| AMS | Extreme's Tracker Module Format |
| AMS | Photoshop Monitor Setup (Adobe) |
| AMS | Velvet Studio Module |
| AMT | ABBYY Finereader 5.0 Pro (ABBYY Software House) |
| AMT | LICOM AlphaCAM 3D Mill, 2D Mill Tool |
| AMT | ArtMoney Table (ArtMoney Team) |
| AMV | MTV Movie File (Anime Music Video) |
| AMW | AMOS Data |
| AMW | WinScript Show Data (Alcorn McBride Inc.) |
| AMX | MetaMOD Half-Life Plug-in |
| AMX | After Effects Motion Exchange File (Adobe) |
| AMZ | The Amazon Trail Saved Game |
| AN | Groundworks Text File |
| AN1 | WWG DA-30 Capture File |
| AN1 | Street Atlas Draw File (Delorme) |
| AN1 | XMap Draw File (Delorme) |
| AN8 | Anim8or 3D Animation |
| ANAT | XNBC V8 Biological Neural Network Simulation Workstation Network Anatomy |
| ANB | Analyst's Notebook Analytical Chart (i2 Ltd.) |
| ANC | Canon Computer Pattern Maker File |
| ANC | LICOM AlphaCAM NC Program |
| AND | Collins Electronic Dictionary Data (Windows) / Concise Oxford Dictionary (DOS) |
| ANF | AcuteNotes |
| ANG | AIMSUN NG Network (TSS-Transport Simulation Systems) |
| ANI | Windows Animated Cursor (Microsoft) |
| ANI | NeroMix File (Nero AG) |
| ANI | NEOchrome Animation |
| ANIM | Amiga IFF Animation (Amiga) |
| ANL | LICOM AlphaCAM Nest List |
| ANL | Project Analyzer Saved Analysis |
| ANL | Annotis Mail Language File (Emeris Technologies) |
| ANL | Eisenbahn.exe Professionell Railroad Track Layout (Software Untergrund) |
| ANM | DeluxPaint Animation |
| ANM | Infinity Equation Script (MathRevolt) |
| ANM | Animatic Animation File |
| ANM | Jazz Jackrabbit 2 Title Sets Images (Epic Games, Inc.) |
| ANN | Help Annotation |
| ANN | King-FIX |
| ANNOT | Amaya Annotation |
| ANO | Annotation |
| ANP | Annotis Mail (Emeris Technologies) |
| ANR | Street Atlas Route File (Delorme) |
| ANR | XMap Route File (Delorme) |
| ANS | ANSI Graphic/Text |
| ANS | Word Text and Layout (Microsoft) |
| ANS | HotDocs Answer File (Matthew Bender & Company, a member of the LexisNexis Group) |
| ANSR | AnswerTool Question/Answer Document (DTLink LLC) |
| ANT | SimAnt for Windows Saved Game File |
| ANT | calcAnt Saved Calculation (SFR GmbH) |
| ANTIFRAG | DC++ Incomplete Download |
| ANV | AirNav |
| ANX | HotDocs Answer File (Matthew Bender & Company, a member of the LexisNexis Group) |
| AO | Free Pascal Archive File for OS/2 Version (FPC Development Team) |
| AOB | DVD Audio File |
| AOF | Acorn Object Format |
| AOI | Art of Illusion Scene File (Peter Eastman) |
| AOL | AOL (America Online, Inc.) |
| AOM | Download Manager Online Manager Shortcut (Adobe Systems Inc.) |
| AOM | After Effects Output Settings (Adobe) |
| AOR | Searchlight AR3000/AR3000A Radio Scanner Frequency Listing (AOR UK LTD) |
| AOS | Nokia Phone Add-on Software (Nokia) |
| AOT | Novell snAppShot Application Binary Object Template File |
| AP | Applix Presents |
| AP | Datalex EntryPoint 90 Data File |
| AP | WHAP-Compressed Amiga Archive |
| AP | ArmPack Archive File |
| AP0 | Windows APW_data File |
| APA | AlfaPad Notes Organizer Document (AlfaAlfa Software) |
| APA | ArcPad Ver. 6 Applet |
| APB | LICOM AlphaCAM Punch VB Macro |
| APB | Avram's PC Backup File List (QuadraSoft) |
| APC | AiroPeek |
| APC | Gupta Team Developer Compiled Application File |
| APC | Lotus Printer Driver Characters (IBM) |
| APC | APAC Compressed Audio |
| APC | Cryo Interactive APC Audio |
| APD | Gupta Team Developer Dynamic Application Library File |
| APD | LICOM AlphaCAM Punch Drawing |
| APD | Lotus Printer Driver (IBM) |
| APD | PageMaker Printer Description (Adobe) |
| APE | Monkey's Audio Lossless Audio Compression Format |
| APE | Winamp Plug-ins AVS File |
| APF | Acrobat Profile File (Adobe) |
| APF | ArcPad Ver. 5 Profile |
| APF | Fax2000 File |
| APF | Homesite Project File |
| APF | Lotus Printer Driver Fonts (IBM) |
| APF | MightyFax File |
| APF | Speedy Printed Circuit Board Design Software (Mania Technologie) |
| APG | PowerAda Aprobe File (OC Systmes) |
| APG | Active Page Generator APG Script (Webgecko Software) |
| APG | Graphic |
| APG | EasyBase Database File (Pg SoftWorkS') |
| API | 1st Reader Passed Parameter File |
| API | Acrobat Plug-in (Adobe) |
| API | Application Program Interface |
| API | Lotus Printer Driver Info (IBM) |
| API | Photoshop Ink Colors Setup (Adobe) |
| API | WebObjects Interface (Apple Computer, Inc.) |
| APIN | InDesign Import/Export Filter (Adobe Systems Inc.) |
| APJ | Angel Debug Monitor Project |
| APJ | ARM Project Manager |
| APJ | Music Screen Saver File |
| APK | GameSpy Arcade Service |
| APL | APL Workspace/Source |
| APL | ArcPad Ver. 6 Layer |
| APL | Gupta Team Developer Application Library File |
| APL | Monkey's Audio Image Link File |
| APM | ArcPad Ver. 6 |
| APM | AutoPlay Menu Studio Configuration (Indigo Rose Software) |
| APM | LICOM AlphaCAM Punch Parameter Macro |
| APM | Aldus Placeable Metafiles (Adobe) |
| APO | Apollo Scripts |
| APO | Paperless Office (Abacre) |
| APP | ArcPad Ver. 5 Project |
| APP | Gupta Team Developer Normal Mode Application File |
| APP | Clarion for Windows Application (SoftVelocity) |
| APP | dBASE Application Object File |
| APP | Executable Application |
| APP | LICOM AlphaCAM Punch Post |
| APP | Lotus Symphony Add-in Application |
| APP | R:Base, Symphony, DR-DOS, FoxPro (or other) Application |
| APP | SymbianOS Application (Symbian Ltd.) |
| APP | Video CD on CD-i Application |
| APP | VTech Helio Application (VTech Holdings Ltd.) |
| APP | Psion Oval Application (Psion PLC) |
| APP | OrbWorks PocketC CE Application |
| APP | Ca Visual Objects Platform for Developer (CAVO) Project File (CA) |
| APPT | Authentica Secure Office Protected PowerPoint Document (Authentica) |
| APR | ArcView Project File (ESRI) |
| APR | Employee Appraiser Performance Review File |
| APR | Approach 97 File (IBM) |
| APR | MicroSim PCBoard Aperture Information Report |
| APR | Various Appraisal Software Appraisal File (PRIMEDIA Business Magazines & Media Inc.) |
| APRJ | ApacheConf Project (Zecos Software) |
| APS | Advanced Patching Systems with Error Checking |
| APS | ArcPad Ver. 5 Symbology |
| APS | Visual C++ File (Microsoft) |
| APS | Flash |
| APT | Gupta Team Developer Text Mode Application File |
| APT | LICOM AlphaCAM Punch Tool |
| APT | Approach Data View File (IBM) |
| APT | Nimbus 7 SAMS Data File |
| APT | appTranslator Project (appTranslator) |
| APV | Speedy Printed Circuit Board Design Software (Mania Technologie) |
| APW | Any Password Password File (RomanLab) |
| APW | Authorware Pro for Windows Packaged FIle (Macromedia) |
| APX | Ability Office Photopaint Image (Ability Software) |
| APX | ArcPad Ver/ 6 XML File |
| APX | C++ Appexpert Database (Borland Software Corporation) |
| APX | Approach Paradox-specific Information File (IBM) |
| APX | TheTomb Browser APX Webfile (Apoltix) |
| AP_ | C Poet Compressed Disk1 File |
| AQ | Applix Data |
| AQ | Ancestral Quest Genealogy File (Incline Software, LC) |
| AQ1 | AptiQuiz Test File (RJ Software) |
| AQA | AptiQuiz Test Result (RJ Software) |
| AQF | Aquifer Content Management System Aquifer-Generated Web Page (Liquid Development, LLP) |
| AQL | AOL Windows DLL (America Online, Inc.) |
| AQM | CP/M Information File |
| AR | Javasoft JRE 1.3 Library File |
| AR | Midtown Madness City Add-on (Microsoft) |
| AR | AIX Small Indexed Archive |
| ARA | ATI Radeon Video Driver |
| ARB | LICOM AlphaCAM Router VB Macro |
| ARC | Archive |
| ARC | Insight II Cartesian Coordinate Archive File (Accelrys Software Inc.) |
| ARC | Schedule+ 1.0 File (Microsoft) |
| ARCH | Illum Source Dotfiles File |
| ARCH00 | F.E.A.R. Game Archive (Monolith Productions, Inc.) |
| ARCHIMEDES | Speccy Snapshot |
| ARCHITECT | London Architect Design File (BSS Audio) |
| ARD | LICOM AlphaCAM Router Drawing |
| ARE | Infinity Game Engine Area Description (BioWare Corp.) |
| ARF | AOL Instant Messenger Resource File (America Online, Inc.) |
| ARF | Automatic Response File |
| ARG | AutoCAD Profile Export (Autodesk, Inc.) |
| ARG | HDF Fort_ps File |
| ARH | Archivers Definitions File (DN) |
| ARH | ArHymo Hydrologic Simulation |
| ARI | Aristotle Audio |
| ARI | Compressed Archive |
| ARJ | Compressed Archive |
| ARJ | Robert Jung ARJ Compressed Archive |
| ARK | Managing Your Money Achive |
| ARK | QuArk Compressed File Archive |
| ARK | CP/M Information File |
| ARL | AOL Organizer (America Online, Inc.) |
| ARLOLD | AOL 6 Organizer (America Online, Inc.) |
| ARM | Armadillo Software Protection System |
| ARM | LICOM AlphaCAM Router Parmeter Macro |
| ARM | Acorn ROM/Disk Image File |
| ARN | Astronomical Research Network |
| ARN | XMap Flight Plan or Flight Plan Statistic File (Delorme) |
| ARO | SteelArrow Web Application Server Script (Tomahawk Technologies) |
| ARP | LICOM AlphaCAM Router Post |
| ARP | Ahsomme Accounting Package Report Layout Template (Simple Solutions) |
| ARPX8 | Techno Toys Arp-X8 MIDI Arpeggiator File |
| ARQ | Compressed Archive |
| ARQ | Remedy Action Request System Client Macro |
| ARR | Amber ARR Bitmap Image |
| ARR | Atari Cubase Arrangement (Steinberg) |
| ARR | Remedy Action Request System Client Report |
| ARR | MicroImages Value Array (MicroImages, Inc.) |
| ARS | Artifax Report Editor |
| ARS | After Effects Render Settings (Adobe) |
| ART | Another Ray Tracer Format |
| ART | AOL Johnson-Grace Compressed File (America Online, Inc.) |
| ART | Art Director Image |
| ART | ARTiSAN |
| ART | Bernina Artista |
| ART | Blood Archive |
| ART | Canon Crayola Art File |
| ART | Canon Crayola Art File |
| ART | Central Point Scrapbook |
| ART | Clip Art File |
| ART | Compressed Archive |
| ART | Duke Nukem 3D Archive |
| ART | First Publisher Raster Graphic |
| ART | LICOM AlphaCAM Router Tool |
| ART | pfs:Art Publisher |
| ART | Vort image |
| ART | Xara Studio Drawing (Xara) |
| ART | ArtCAM Pro and ArtCAM Insignia Model Data (Delcam plc) |
| ARV | Arsiv |
| ARV | AutoRoute User Information (Microsoft) |
| ARV | Eschalon Setup Archive (Eschelon Development (24-2979 Panorama Dr., Coquitlam BC V3E 2W8, Canada)) |
| ARX | AutoCAD Runtime Extension (Autodesk, Inc.) |
| ARX | ARX Compressed Archive |
| ARY | Compaq SmartStart Scripting Toolkit File |
| AS | Applix Spreadsheet |
| AS | Macromedia Flash Action Script |
| AS | Dispatch Alaska/Horizon Timetable File (Scott Andrew Borton) |
| AS | AppleSingle Encoded File (Apple Computer, Inc.) |
| AS3 | Alternate Sources Data |
| AS3 | APL*PLUS II/386 and III/Windows Source Code |
| AS4 | AS/400 Client Access |
| ASA | Active Server Document |
| ASA | Visual InterDev File (Microsoft) |
| ASAX | ASP.NET Source File (Microsoft) |
| ASB | LICOM AlphaCAM Stone VB Macro |
| ASC | ASCII Text |
| ASC | Pretty Good Privacy (PGP) Armored Encrypted File (PGP Corporation) |
| ASC | 3D Studio 3D Scene (Autodesk, Inc.) |
| ASCX | Web User Control (Microsoft) |
| ASD | Advanced Streaming Format Description (Microsoft) |
| ASD | Astound Presentation |
| ASD | LICOM AlphaCAM Stone Drawing |
| ASD | Lotus Screen Driver (IBM) |
| ASD | Word Automatic Backup (Microsoft) |
| ASD | Origins Embroidery Design (Origins Software Technologies, Inc.) |
| ASE | Velvet Studio Sample |
| ASF | Advanced Streaming Format (Microsoft) |
| ASF | APL*Plus/PC APL Shared File |
| ASF | Electronic Arts Music File (Electronic Arts, Inc.) |
| ASF | Lotus Screen Font (IBM) |
| ASF | STATGRAPHICS Data File (Manugistics, Inc.) |
| ASF | FIFA Football 2004 Audio File (Electronic Arts, Inc.) |
| ASG | Airport Tycoon Saved Game (Global Star Software) |
| ASH | TASM Assembler Header |
| ASH | Sony DSC-F828 Firmware Upgrade File (Sony) |
| ASHDISC | Burning Studio Disc Image File (Ashampoo GMBH & Co.) |
| ASHPRJ | Burning Studio Project (Ashampoo GMBH & Co.) |
| ASHX | ASP.NET Web Handler File |
| ASI | Assembler Include (Borland Software Corporation) |
| ASIC | ASIC Language Source Code |
| ASJ | Aldfaer |
| ASK | askSam Database |
| ASK | Astrotite Skin (Fantiusen Software) |
| ASK | Ad-Aware Skin File (Lavasoft) |
| ASL | Asmodo 9s |
| ASL | Photoshop Layer Style (Adobe) |
| ASL | Quest Adventure Game (Axe Software) |
| ASL | AppSight Console Log (Identify Software Ltd.) |
| ASM | Assembler Source Language |
| ASM | LICOM AlphaCAM Stone Parameter Macro |
| ASM | Pro/ENGINEER Assembly File (PTC) |
| ASM | Solid Edge Document (UGS PLM Solutions) |
| ASMX | ASP.NET Webservices Source |
| ASN | Asn |
| ASN1 | Asn Specs |
| ASO | Assembler Object |
| ASO | Astound Dynamite Objects |
| ASP | Active Server Page |
| ASP | ASAP WordPower WebShow presentation |
| ASP | Astound Presentation |
| ASP | EROSION 3D Aspect File |
| ASP | LICOM AlphaCAM Stone Post |
| ASP | Photoshop Photo File Index (Adobe) |
| ASP | Photoshop Separation Setup (Adobe) |
| ASP | Procomm Plus ASPECT Program |
| ASP | Software Publishing Corp. |
| ASP | Terminal Program |
| ASP | Text Data |
| ASPHTML | ASP HTML (Microsoft) |
| ASPI | Audio Catalyst |
| ASPR | ASProtect (ASPACK SOFTWARE) |
| ASPX | ASP.NET Source File (Microsoft) |
| ASR | Streets & Trips Route (Microsoft) |
| ASR | Photoshop Scratch Area (Adobe) |
| ASS | ASS I/O |
| ASS | Assembler/Disassembler 68HC11 |
| ASS | Assistance for the Blind |
| ASS | Flash |
| ASS | Aegisub Advanced SubStation Alpha Subtitle File (Rodrigo Braz Monteiro) |
| ASSOC | Associate This File Association Database (Spearit) |
| AST | Astound Multimedia |
| AST | Claris Works Assistant File |
| AST | Photoshop Separation Tables (Adobe) |
| AST | Technics Sx KN 6000 Keyboard All Custom Memory File |
| AST | Need for Speed: Underground Audio File (Electronic Arts, Inc.) |
| AST2 | Astrotite (Fantiusen Software) |
| ASV | DataCAD Autosave File (DATACAD LLC) |
| ASV | Photoshop Selective Color (Adobe) |
| ASV | QuarkXpress Auto Save File (Quark, Inc.) |
| ASV | MATLAB Autosave File (The MathWorks, Inc.) |
| ASV | Pegasus Mail Auto Saved Message (David Harris) |
| ASV | NotePad 2004 (Finale) |
| ASWCS | avast! Antivirus Skin (ALWIL Software) |
| ASWS | avast! Antivirus Skin (ALWIL Software) |
| ASX | Advanced Stream Redirector File (Microsoft) |
| ASX | Cheyenne Backup Script |
| ASX | ActiveSite Extension (Jonathon Rossi) |
| ASX | Alpha Five Temporary Index (Alpha Software, Inc.) |
| ASY | LTspice/SwitcherCAD III Circuit Diagram (Linear Technology) |
| AS_ | Winhelp Compressed File |
| AT | Rescue Disk file |
| AT2 | WinControl DCX-AT3000 Motion Control Command Language File (Precision MicroControl Corp.) |
| AT2 | Persuasion Ver. 2.0 Auto Template (Adobe) |
| AT3 | WinControl DCX-AT3000 Motion Control Command Language File (Precision MicroControl Corp.) |
| AT3 | Airport Tycoon Version 3 Saved Game (Global Star Software) |
| AT3 | PSP Audio File (Sony) |
| ATB | LICOM AlphaCAM Lathe VB Macro |
| ATB | TechMed Annotation ToolBar (TechMed) |
| ATC | Sniffer Capture File (Network Associates Technology, Inc.) |
| ATC | AutoCAD Catalog (Autodesk, Inc.) |
| ATC | AceText Collection (JGsoft - Just Great Software) |
| ATD | LICOM AlphaCAM Lathe Drawing |
| ATD | MS Systems Management Server SMSADDIN.EXE tool registration |
| ATF | Photoshop Transfer Function (Adobe) |
| ATF | Sharp APL Workspace Export File |
| ATG | Netmino File |
| ATH | LICOM AlphaCAM Lathe Thread |
| ATK | Andrew Toolkit Raster Object Bitmap |
| ATL | Hal/Supernova/Lunar/LunarPlus Screen Readers/Magnifiers |
| ATL | PROGNOSIS Atlas Document File |
| ATL | ATP Assembler Source (Brancepeth Computer Publications) |
| ATM | LICOM AlphaCAM Lathe Parameter Macro |
| ATM | Terragen Light and Atmosphere (Planetside Software) |
| ATM | Type Manager Data File (Adobe) |
| ATM | .nugthat Player (Nuggets Unlimited, Inc.) |
| ATM | The Universal 3D Model/Texture File (The Universal Development Team) |
| ATMN | Automation Anywhere Automation Macro (Tethys Solutions, LLC.) |
| ATMSPHR | TerragGen Atmosphere (Planetside Software) |
| ATN | Photoshop Action File (Adobe) |
| ATO | Just Burn File (Sonic Solutions) |
| ATOM | .nugthat Player (Nuggets Unlimited, Inc.) |
| ATP | LICOM AlphaCAM Lathe Post |
| ATP | Visual Studio .NET ACT Project (Microsoft) |
| ATP | ATRAC Coded File |
| ATP | Anti Tracks Plug-in (RIGHT Utilities, Inc.) |
| ATR | Lightscape Material Library |
| ATR | MicroSim PCBoard Attributes Report |
| ATR | Atari Disk Image File (Atari) |
| ATS | Attityd Swedish Survey Program |
| ATS | Unrelated Inventions Audiotools Plug-in |
| ATT | AT&T Group 4 Bitmap (fax) |
| ATT | LICOM AlphaCAM Lathe Tool |
| ATT | ZipLip Secure E-mail |
| ATT | SeeYou Waypoint (Naviter) |
| ATT | Web Form Data (POSTDATA.ATT) |
| ATW | AnyTime Deluxe PIM File |
| ATW | Attityd Swedish Survey Program |
| ATX | A ZIP-formatted Compressed Archive |
| ATX | Alphasoft Trueterm 2001 Dictionaries |
| AT_ | Audio Utility Winatb Compressed File |
| AU | uLaw/AU Audio File |
| AU | Audacity Audio Block |
| AU3 | AutoIt Ver. 3 Script (HiddenSoft) |
| AUD | Audio File used by Westwood Studios for various games |
| AUD | DTS Audio Data Stream (Digital Theater Systems Inc.) |
| AUD | Winamp Media File (Nullsoft) |
| AUF | LICOM AlphaCAM User Font |
| AUF | ASAUpdaterV2 Update File (ASA Datec Datensystem GmbH) |
| AUP | ePocrates File |
| AUP | Audacity Project File |
| AUR | Sheffield Thesaurus file |
| AUR | AutoREALM Map |
| AUS | Agnitum Outpost Firewall Configuration |
| AUS | AutoREALM Symbols |
| AUT | Authentication File |
| AUT | AutoIt (pre Ver. 3) Script (HiddenSoft) |
| AUT | Descent Manager Mission File |
| AUT | GPSMan-autoMapic File |
| AUT | Interactive Pictures iPIX Format |
| AUT | PocketWear Car Lease Kit Vehicle Data File |
| AUT | Signwave Auto-Illustrator File |
| AUT | TLG Workplace CD Search File |
| AUT | Xitami Webserver Admin Password File |
| AUT | AUTHOR eLearning Module (Microcraft) |
| AUT | Autostart Adware Malware |
| AUTOCONF | UNIX File |
| AUTOREG | Mozilla (Netscape) Auto Registration Clue (Mozilla.org) |
| AUX | ChiWriter Auxilliary Dictionary File |
| AUX | TeX/LaTeX Auxilliary Reference File |
| AUX | ArcGIS Auxiliary File for GIS Datasets (ESRI) |
| AV | Final Draft AV Document File |
| AVA | Avagio Publication |
| AVA | Photoshop Variations File (Adobe) |
| AVB | Avid Bins File |
| AVB | Chat Character File (Microsoft) |
| AVB | Inoculan Anti-Virus Virus Infected File |
| AVC | Kaspersky Antivirus Toolkit File |
| AVD | DOS7 File |
| AVD | Label Pro Data (Avery) |
| AVE | ArcView Avenue Script (ESRI) |
| AVF | AccountsVision Workbook (AccountsVision Ltd) |
| AVG | Grlib Urt Get Getami File |
| AVG | AVG Virus Information Database (Grisoft) |
| AVI | Audio Video Interleave File |
| AVL | ArcView Theme Legend File (ESRI) |
| AVL | Video Fun File |
| AVM | AVISO Geographic Information System Map File (Wojciech Pomianowski) |
| AVP | ArcView Pallet File (ESRI) |
| AVP | Avid Project |
| AVR | Audio Visual Research Sound |
| AVS | Animation |
| AVS | Application Visualization System Format |
| AVS | Avid Settings |
| AVS | Avisynth |
| AVS | Stardent AVS X Image |
| AVS | Winamp Advanced Visualization Studio (Nullsoft) |
| AVT | A3E Avatar-coding File |
| AVX | ArcView Extension File (ESRI) |
| AVX | Avid Extensions |
| AW | Answer Wizard (Microsoft) |
| AW | Applix Word |
| AW | HP AdvanceWrite Text File |
| AW | Free Pascal Archive File for Windows Version (FPC Development Team) |
| AWA | Animation Works Accelerated Movie |
| AWA | ActiveWords Application (ActiveWord Systems, Inc.) |
| AWB | Ad-Aware Backup File (Lavasoft) |
| AWB | ActiveWords WordBase (ActiveWord Systems, Inc.) |
| AWB | Adaptive Multi-Rate Wideband ACELP codec |
| AWBS | Automated Weight and Balance System (AWBS) Data Storage File (Lockheed Martin Corporation) |
| AWD | Award BIOS |
| AWD | AWK Source Code |
| AWD | FaxView Document (Microsoft) |
| AWE | Acrobat Bookmark XML File (Adobe) |
| AWF | Qui veut gagner des millions Archive |
| AWF | Who Wants to be a Millionaire Archive |
| AWH | ActiveWorlds Browser Help File (Activeworlds, Inc.) |
| AWK | AWK Script |
| AWL | Ad-Aware Language File (Lavasoft) |
| AWM | AllWebMenus |
| AWM | Animation Works Movie |
| AWM | RenderWare Language Pack (Criterion Software) |
| AWP | Akimbot Waypoint File |
| AWP | MS Fax Key Viewer |
| AWP | ActiveWords Productivity Log (ActiveWord Systems, Inc.) |
| AWR | Ad-Aware Reference File (Lavasoft) |
| AWR | Telsis Digital Audio File |
| AWS | AutoCAD Work Space (Autodesk, Inc.) |
| AWS | ActiveWords System File (ActiveWord Systems, Inc.) |
| AWSHORTCUT | ActiveWords Shortcut (ActiveWord Systems, Inc.) |
| AWT | AlbumWeb |
| AWW | Ability Office Write Document (Ability Software) |
| AWW | AWW WML Website Administrator Configuration File |
| AWX | Custom Application Wizard |
| AWX | DirectX 8.1 (Microsoft) |
| AWX | Fax |
| AWZIP | ActiveWords Compressed Solution (ActiveWord Systems, Inc.) |
| AW_ | Quartz Sets Compressed File |
| AX | DirectShow Filter |
| AX | Modula-3 Linker Information for Libraries |
| AX | MPEG-4 DVD Filter |
| AX | ATI DA Interface Handler (ATI Technologies Inc.) |
| AXD | Actrix Technical 2000 (Autodesk, Inc.) |
| AXD | Label Pro Re-Index (Avery) |
| AXE | AutoRoute Export File (Microsoft) |
| AXE | ChordMaster |
| AXE | Pchord Powpro Compressed File |
| AXE | Paradigm C++ Integrated Debugger File |
| AXF | Mira File List (Mirametrics, Inc.) |
| AXG | AutoRoute Trip File (Microsoft) |
| AXI | Axiom Composite File Management System |
| AXI | MetaToolsFile Kai's Power Goo Picture Library |
| AXL | ArcIMS XML Project |
| AXLS | Authentica Secure Office Protected Excel Document (Authentica) |
| AXP | GraphStore eCADLite File |
| AXP | AppGini MySQL Code Generator Project (BigProf Software) |
| AXP | AnvilCad CAD File (Manufacturing and Consulting Services (MCS), Inc.) |
| AXQ | Ada ADA Editor File |
| AXR | ElcomSoft Advanced Archive Password Recovery |
| AXR | Telsis Digital Audio File |
| AXR | AXIS Diplomat Report File (Systems AXIS Ltd.) |
| AXS | HTML; ActiveX Script |
| AXS | MindAvenue AXEL Stream File |
| AXT | Photoshop Replace Color/Color Range (Adobe) |
| AXT | ZenWorks snAPPshot ASCII Application Object Template |
| AXX | AxCrypt Encrypted File (Axon Data) |
| AY | AY Chip Sound (Project AY) |
| AY | Dispatch Finnair Timetable File (Scott Andrew Borton) |
| AYA | RPG-Maker2000 Project Launcher Saved Game File |
| AYM | Z80 Music Code With AY Music |
| AYS | AY Paste Paste File |
| AYU | AY-Paste Uninstall Information |
| AZ | WinDVD File |
| AZM | CP/M Disk Fix File |
| AZZ | AZZ Cardfile Personal Information Manager |
| A_T | Atrain |