The Local Area Network
Even if you don't plan on letting the big, bad Internet anywhere near your PCs, a home network still has many uses. Many of the basics of setting up the two types of networks are the same. In fact, even if you are planning on sharing a broadband connection, the place to start is right here. Don't skip to the next section without getting the items in here working first. The best approach I've found for creating a broadband connection sharing network is to start with a working LAN and then add the Internet connection.
A typical Internet Service Provider (ISP) will supply the connection to the Internet through some device that converts their wiring coming into your home (be it cable, copper telephone wires for DSL, fiber optics cable or something else) into a standard network drop. They often also include - either separately or as part of the same device - a router & firewall with one or more ports for your LAN to connect to. That's generally where their work and responsiblity stops. If you have more than one computer to connect to their equipment, that part is left as an exercise for you. That's the viewpoint from which these pages were written, and if you're trying to create a working home network using them, your journey will be more blissful if you proceed in the same manner.