A file extension, or file name extension, is the letters immediately shown after the last period in a file name. For example, the file extension.txt has an extension of .txt. This extension allows the ...

BearPup sometimes wants to open a file in one program, and other times open it in another. He asked the Answer Line forum for an easy way to do this. Windows uses a file’s extension–the part of the ...

Mac OS X computers use a default application to open every file type based on its file extension. If you don't want to use the default application when opening a file, you can select "Open With" from ...

Every file that we have saved on our computers has a particular extension. The file extension is added at the end of the filename followed by a dot (.). It tells the operating systems about the ...