telnet and file names

I am a linux beginner (just graduated from idiot).  I have written a PC App 
which provides a nice graphical Telnet capability that allows for navigation 
through the HD1K File world.  It implements ls, cat, cp, mv, mkdir, rm in a 
simple graphical manner plus basic telnet ability.  Working with it so far I 
have not harmed my HD1K. It has brought me to some questions.  

If I do a cat /mnt/flash0/etc/rc.local the file appears to be empty.  Is that 
correct? I thought this was the system initialization file and would have had 
some stuff in it.

The actual file name is suffixed with an "@" (rc.local@). If I do a 
cat /mnt/flash0/etc/rc.local@ a diagnostic is returned saying the file does 
not exist. What is the meaning of the trailing "@"?

What are the other file name suffixes and what do they signify?.

If a do a cat /mnt/flash0/home/root/.bash_history the response is the listing 
of a file named "/mnt/flash0/etc/smb.conf*". I am assuming they are aliases 
i.e. .batch_history is an alias for smb.conf.  Am I correct?

What is the significance of the suffix "*" on the file name smb.conf?

A recommendation on a book that explains all of this would probably get me 
educated faster and be less of an imposition on the good guys.  I have some 
Linux books, but I can not find the info I am looking for.

If anyone wants a copy of the app, or my artPack builder app, drop me a line 
at [email protected].  Both are in Alpha/beta state and without 
documentation but fairly obvious if you have explored PC based Apps. (read ini 
files, click on things, double click on things . . .) 

Thanks in advance

Barry