A Network can be as simple as two computers sharing one internet connection through either wired or wireless. It can also be a server network where one computer acts as a server supporting many other computers in an office.
Setting up a network is a great way to get more use out of your computers and peripherals. With a network, you can:
Share a single Internet connection among multiple computers
Share files among computers
Use a printer connected to a different computer
Play recorded TV, videos, and digital music stored on your computer from your Xbox 360 or Playstation 3