File name classifications (need answer ASAP thanx)

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Author: plug-discuss@lists.plug.phoenix.az.us
Date:  
Subject: File name classifications (need answer ASAP thanx)
I am trying to figure out what a classification such as @ or * means at the end of a file name. here are a few examples....

allcm*
allec@
control/

if you could tell me what those *, @, and / means at the end of a file it would be greatly appreciated. Other marks I know of are | and = thanks again

chris