What Is a Network?

A network is nothing more than two or more computers connected by a
cable (or in some cases, by a wireless connection) so that they can exchange
information.
Of course, computers can exchange information in other ways besides networks.
Most of us have used what computer nerds call the sneakernet. That’s
where you copy a file to a diskette and then walk the disk over to someone
else’s computer. (The term sneakernet is typical of computer nerds’ feeble
attempts at humor, and why not? As a way to transfer information, sneakernet
was pretty feeble.)

The whole problem with the sneakernet is that it’s slow — plus, it wears a
trail in your carpet. One day, some penny-pinching computer geeks discovered
that connecting computers together with cables was actually cheaper than
replacing the carpet every six months. Thus the modern computer network
was born.
You can create a computer network by hooking all the computers in your office
together with cables and installing a special network interface card (an electronic
circuit card that goes inside your computer — ouch!) in each computer
so you have a place to plug in the cable. Then you set up your computer’s
operating-system software to make the network work, and — voilà — you have
a working network. That’s all there is to it.
If you don’t want to mess with cables, you can create a wireless network
instead. In a wireless network, each computer is equipped with a special wireless
network adapter that has little rabbit-ear antennas. Thus, the computers
can communicate with each other without the need for cables.