Well you first need to set up a LAN ( Local Area Network ). You can do that by use of an Router. A router is a way for the computers to share resources with each other, and share the same internet connection between all of them. The kind you see in peoples houses really compose of routers (or local hubs), ethernet cabling, computers (or 1 PC acting as a server), and more advanced ones may have RAID storage. RAID provides redundant backup for data. I use my walk in closet as a server room. I have a file server in a corner with a wireless and wired routers inter-connected. This allows me to have wifi and wired connections with my systems. The server rooms that large businesses have are built are full of computers that utilize hot swappable drives and are mounted on racks. At the company I work at we process alarm signals so we have a lot of alarm receivers (which process incoming calls from alarm panels), and dozens of mounted computers which handle the database end.