File extension

A file extension is nothing more than the last characters after the period in the name of a file.

FILExt is a database of file extensions and the various programs that use them. If you know the file extension you want to learn about simply enter it into the search box on the left and click on the Search button. If it's in any of the FILExt databases the data we have on that file extension will be shown on a results page. If it's not in any of the databases you will be given a link to a page with hints on how to do further research. Don't search on terms; just file extensions and only one at a time please. There will be another search box on the results page if you have multiple searches to do.
It's possible that the search will give you multiple results as there is no central registry for file extensions. If so, you will have some detective work to do; read the results page carefully as there will be hints on how to do this detective work.
Can I Make Coming to FILExt Easier?
Yes. If you find FILExt useful you can come here to the proper search page using a variety of methods...
Come directly from Windows. Use FILExt Direct to change your registry so you come here when you click on a file Windows does not know how to open.
Come via Google Toolbar. Add a button to your Google toolbar so when you highlight a file extension and click on the button you come directly to FILExt with your search.
Come via Firefox Search. Add FILExt to your Firefox search box and come directly via a search box entry.
Use a Google Desktop Gadget. FILExt has a Google Desktop Gadget which allows you to add basic search to your desktop with links to specific pages once you've found what you want.

Latest Additions/Modifications

XPS XML Paper Specification
HDTV High-Definition Television
IRC Internet Relay Chat
Cyberloafing Doing non-work activities at work on a computer.
Cuckoo Egg A munged copy of what appears to be copyright-protected material.
IPTV Internet Protocol Television
Port Knocking Pinging a combination of ports before entry is allowed.
TIFF Tagged Image File Format
FAHQT Fully Automatic High-Quality Translation
Mashup Web site or application developed from combinations of content.
A/D = Analog to Digital
A/V = Audio/Visual
AAC = Advanced Audio Coding
AARP = AppleTalk Address Resolution Protocol
ABBH = Average Bouncing Busy Hour
ABC = Atanasoff-Berry Computer
ABEND = Abnormal End
AC = Alternating Current
ACD = Automatic Call Distributor
ACeS = Asia Cellular Satellite System
ACK = Acknowledge Character
ACL = Access Control List
ACM = Association for Computing Machinery
ACPI = Advanced Configuration and Power Interface
ACTA = America's Carriers Telecommunications Association
ACU = Automatic Calling Unit
ADB = Apple Desktop Bus
ADCCP = Advanced Data Communications Control Protocol
ADO = ActiveX Data Objects
ADP = Automatic Data Processing
ADPCM = Adaptive Differential Pulse Code Modulation
ADS = Alternate Data Streams
ADSL = Asymmetric Digital Subscriber Line
ADVEIS = Anti-Virus Dependent Vulnerabilities in E-mail Infrastructure Security
AES = Asynchronous Event Scheduler
AFAIK = As Far As I Know
AGP = Accelerated Graphics Port
AH = Authentication Header
AI = Artificial Intelligence
AIFF and AIFF-C = Audio Interchange File Format
AIML = Astronomical Instrument Markup Language
AIX = Advanced Interactive Executive
ALGOL = Algorithmic Language
ALU = Arithmetic (and) Logic Unit
AMANDA = Advanced Maryland Automatic Network Disk Archiver
AMD = Advanced Micro Devices
AML = Astronomy Markup Language
AMP = Advanced Metal Powder
AMPS = Advanced Mobile Phone System
AMS = American Mobile Satellite Corporation
AN = Active Network
ANSA = Adaptive Network Security Alliance
ANSI = American National Standards Institute
AOL = America Online
APA = All Points Addressable
API = Application Program(ming) Interface
APM = Advanced Power Management
APP = Application Portability Profile
APWG = Anti-Phishing Working Group
ARLL = Advanced Run Length Limited
ARM = Advanced (Acorn) RISC Machine
ARM = Advanced RISC Machines Ltd
ARP = Address Resolution Protocol
ARPA = Advanced Research Projects Agency
ARQ = Automatic Repeat Request
ASAP = Activate Secure Authentication Protocol
ASAP = As Soon As Possible
ASCII = American Standard Code for Information Interchange
ASF = ActiveMovie Streaming Format
ASIC = Application-Specific Integrated Circuit
ASP = Active Server Pages
ASP = Application Service Provider
ASP = Association of Shareware Professionals
AT = Attention
ATA = AT Attachment
ATL = Active (ActiveX) Template Library
ATM = Asynchronous Transfer Mode
AUI = Attachment Unit Interface
AVI = Audio/Video Interleaved format
AWHFY = Are We Having Fun Yet
AWT = Abstract Windows Toolkit
CDMA = Code Division Multiple Access
CDPD = Cellular Digital Packet Data
CD-PROM = Compact Disc-Programmable Read Only Memory
CD-R = Compact Disc-Recordable
CDRAM = Cached Dynamic Random Access Memory
CD-ROM = Compact Disc, Read Only Memory
CD-RW = Compact Disc-Rewritable

Where virus affects

Viruses can infect a number of different portions of the computer's operating and file system. These include:
System Sector VirusesThese infect control information on the disk itself.
File VirusesThese infect program (COM and EXE) files.
Macro VirusesThese infect files you might think of as data files. But, because they contain macro programs they can be infected.
Companion VirusesA special type that adds files that run first to your disk.
Cluster VirusesA special type that infects through the disk directory.
Batch File VirusesThese use text batch files to infect.
Source Code VirusesThese add code to actual program source code.
Visual Basic WormsThese worms use the Visual Basic language to control the computer and perform tasks.