Network-specific gear

If you go to your favorite electronics store and look at the aisle that has routers, hubs, and switches in it, you'll notice that they look about the same but hubs are cheaper. That's because hubs are also the simplest option.

Hubs

In essence, a hub is like a car's radio: Everyone who's connected to that channel (or section of network) can hear everything that's being transmitted. Every computer that connects to a hub receives all of the information that goes through the hub, and the hub depends on the existence of a more advanced piece of network software (such as a router) to work correctly. The hub can't assign network locations to computers; it simply broadcasts whatever is fed into it.

Switches

A switch is a bit more complicated. A switch is like a two-way radio; in a room full of people, only the person holding the other radio can hear what's said. The switch keeps track of which computers are connected to which ports, and when network traffic comes in, it sends the information along to only that computer, rather than to all computers on the network. It's both faster and more secure. But it's not as powerful as a router; like a hub, a switch depends on the existence of some more sophisticated piece of equipment to identify the computers that are connected to it.

Routers

A router is like a telephone system. Each computer is given its own unique number by the router. The information comes in, is identified and processed, and then is sent along to the correct location. Along the way, decisions take place behind the scenes in order to determine which is the correct phone number (or computer) to connect with. There are more control options built into a router than into a switch, including networking equivalents of call screening and caller ID.

In practice

With the assistance of a typical broadband firewall-router from the electronics store, you'll have a home network that's distinct from the rest of the Internet. Your computers will be recognized by the router, and the router will assign them IP addresses (the computer version of a telephone number).

Your computers can communicate with each other within the private area that's "shielded" by the router's firewall, and each computer can also make a connection out to the Internet. But thanks to the firewall, external computers won't be able to enter your local network and access your computers without permission.

So when you open a file on Laptop and send it to Desktop's printer, the network information never leaves your local network. The router receives the network packets, recognizes that the packets are addressed to the number it assigned to Desktop, and sends the packets on to Desktop. Desktop receives the packets, recognizes that they're printing instructions, and prints your file.

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