This is a listing of common and standard file extensions. Most uncommon and non-standard file extensions are not listed here. The ones that are have such a label in parenthesis. Many of these are Windows specific.
Extension Type/Description Popular programs that support extnsion
.arj
Arj archive
Arj, Unarj, Winzip
.art
AOL image format (uncommon/non-standard)
AOL
.avi
audio video file
(Default), Activemovie
.au .snd
Audio sound file (uncommon)
(Default)
.bat
DOS batch file
(Default)
.bmp
bitmap
ACDSee , Lview
.c
C program source file
Borland C, Microsoft C
.cab
Microsoft Backup
(Default), cabview
.cda
CD Audio Track
(Default)
.cfg
Configuration file (non-standard)
notepad, editpad, plain text editor)
.com
Command interpreter
(Default)
.cpp
C++ program source file
Borland C++, Microsoft C++
.dll
Dynamic Link Library / Application Extension
(Default)
.doc
text document
(Default), Wordpad
.ecc
Unix image format
*Special viewer*
.exe
executable program
(Default)
.hlp
Help File
(Default)
.htm .html .shtml
Hypertext document
Netscape, Internet Explorer, Mosaic
.inf
setup information
(Default, right click)
.ini
configuration file (generally for Win 3.1)
Any text editor, preferably plain text
.jpg .jpeg
jpeg image
ACDSee, Lview
.lnk
Win95 shortcut file
(Default)
.lzh
lzh archive
Lha, Lhasa
.mid .midi
midi music file
(Default)
.mp3
mpeg layer-3 audio file
Winamp
.mpg .mpeg
audio/video file
(Default), Activemovie, Vmpeg, Xing
.mov
Quicktime movie
Quicktime
.nfo
text document
Any word processor
.pcx
image file
(Default), Lview
.png
image file
ACDSee
.ps
Postscript File
Ghostview
.qm
Quality Motion video
Quality Motion Player
.qt
Quicktime Movie
Quicktime
.ra .rm .ram
RealPlayer audio video
RealPlayer
.reg
Registration Entry
(Default)
.scr
Screen Saver
(Default)
.sys
System File
(Default)
.tar
Tar archive (Unix)
Winzip
.txt
Plain text
(Default), notepad, editpad
.rar
Rar archive
Rar, Unrar, Winrar
.url
Internet Shortcut
Internet Explorer
.wav
audio file
(Default Player)
.zip
Zip archive
Winzip, Pkunzip, Pkzip
Extensions not listed: Adobe Acrobat.
