[X Newbies] app extensions?

[VS]

At 22.58 -0800 03-12-04, Robert (Bob) P. Andris wrote:
>Does anyone know of a list of app extensions?  I was given some 
>files that end in ".p65" and some that end in ".ai".  Trying to find 
>something that will open them.

.ai is Adobe Illustrator, that is my strongest guess.
There are some places on the webb where you can look up extensions, 
here is one such place.
http://whatis.techtarget.com/fileFormatA/0,289933,sid9,00.html

As this is a returning problem for me as well I am grateful for tips 
on other such sites.

/ Vicki
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