network file sharing

I know very little about networking. I've had my 3 computers in my house (all running XP Home) networked, but we want every computer to be able to change files in the other computers. Someone told me to make the hard drive of the main computer "shared" by hitting "Sharing and Security" when you right click the hard drive. Under the sharing tab, it says that there's a risk if I choose this option. What's the risk? Can people on the internet access my hard drive then or just the other computers in my house? How can I tell which things can access my computer?

My advise: never share your complete hard drive!
If you have a firewall running on your router, then you
are more secure.
If not, then all shares on your LAN are also accessible
from the internet....something you do not want I
suppose...
Have a look here: http://www.practicallynetworked.com/
There very good info here...
>-----Original Message-----
>I know very little about networking. I've had my 3
computers in my house (all running XP Home) networked,
but we want every computer to be able to change files in
the other computers. Someone told me to make the hard
drive of the main computer "shared" by hitting "Sharing
and Security" when you right click the hard drive. Under
the sharing tab, it says that there's a risk if I choose
this option. What's the risk? Can people on the
internet access my hard drive then or just the other
computers in my house? How can I tell which things can
access my computer?
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