Newbie at networks

Hi,

Please forgive my ignorance, however i am a newbie at networking.
I was wondering if it is possible to set up a network, or a network drive between two computers in different locations (i.e. in two different cities) that could share information....or use remote access to control the other computer etc etc, one is on XP and one is on Vista. Also do both computers need to be switched on to access this information? please could anyone shed some light on how to do this if it can be done?

Thanks in anticipation

Yes, it can be done. You should explain in more detail what you want to do though. The solutions for different needs are vastly different.

basically i want to be able to use sage from home whilst someone at the office can still use it for inputting orders/invoices etc, and be able to both use sage without having to "save backup" and "restore" everytime one of us has made changes.......
I want to be able to access the financials etc as a manager

Thank you for your help

currently using Sage accounts V12