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PC File Extensions

A file extension is 1,2, or 3 characters which end after a file name used to identify the program used to run the file with.


Open With is a feature included in Windows 95, 98, NT and 2000. This feature will appear when Windows does not know how to open the file you have attempted to execute. Using this program the user can locate the appropriate file used to open the file you are attempting to open.
To help determine what program should be used to open the file right click on the file and choose properties. Within properties look at the MS-DOS name this name should contain a file name and then an extension such as myfile.txt, in this case the .txt is the extension of the file. TXT files are generally text files which are opened with wordpad or notepad.
Keep in mind that a lot of files may be data files and do not necessarily need to be opened. 


     1. In MS-DOS when typing dir to list all files each file will end with an extension.

     2. In Windows 98 open My Computer / choose View / Folder Options / uncheck the box which
         says "Hide file extensions for known file types" / Apply / OK

To view the file extension listing and which program is commonly used to execute that extension click on one of the links below.

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