Common Windows file extensions
Windows file names have two parts, the name, then a period and the extension (suffix). The extension is a three- or four-letter abbreviation that comes after the period. For example, in letter.doc the filename is letter and the extension is doc.
Extensions are important because they tell your computer what icon to use for the file, and what application can open the file. For example, the doc extension tells your computer that the file is a Microsoft Word file.
If you want to open a MAC OS X file in Windows, you may need to add the extension to a MAC OS X file name so Windows can recognize it. For example, if you have a Word 6 MAC OS X document named letter that you want to open in Windows, you need to rename the file letter.doc so that Word in Windows will recognize and open the file.
The list below explains some of the common extensions.
Note: This list is by no means a complete and exhaustive list of file extensions. If the file extension you are using is not listed below, you may find the information by looking in the software manual or software application's Web site.
Note: If none of your file names have extensions, file extensions are hidden. See
|File Extension||File Type|
|.AIFF or .AIF||Audio Interchange File Format|
|.BAT||PC batch file|
|.CLASS or .JAVA||Java files|
|.CSK||ClarisWorks for Windows|
|.DBF||dbase II, III, IV data|
|.DIF||Data Interchange format|
|.DOC||Microsoft Word for Windows/Word97|
|.FM3||Filemaker Pro databases (the numbers following represent the version #)|
|.GIF||Graphics Interchange Format|
|.HTM or .HTML||Web page source text|
|.JPG or JPEG||JPEG graphic|
|.MAP||Web page imagemap|
|.MDB||MS Access database|
|.MID or .MIDI||MIDI sound|
|.MOV or .QT||QuickTime Audio/Video|
|.MTB or .MTW||MiniTab|
|Acrobat -Portable document format|
|PageMaker (the numbers following represent the version #) P=publication, T=template|
|.PNG||Public Network graphic|
|.RTF||Rich Text Format|
|.SIT||Stuffit Compressed Archive|
|.TAR||UNIX TAR Compressed Archive|
|.TXT||ASCII text (Mac text does not contain line feeds--use DOS Washer Utility to fix)|
|.WK3||Lotus 1-2-3 (the numbers following represent the version #)|
|WPD or .WP5||WordPerfect (the numbers following represent the version #)|
|.ZIP||PC Zip Compressed Archive|
Showing File Extensions
If none of your file names have extensions, file extensions are hidden. To show file extensions:
- Click on the start menu, and type "Show hidden files and folders," then press the enter key.
- Click on the "View" tab, and make sure Hide extensions for known file types is not checked.
- Click "Apply" then "OK".