File sharing allows you to access part or all of another Macs hard drive as if it were physically a part of that machine. When you access the other computers hard drive, it shows up on your desktop just like any other drive or disk. More than just file sharing. There are also a number of other things that you can do with a network. Other than file sharing I have a feeling that the second most frequent use of networks are for network computer games .
Many games have the capability for two or more people to play with or against each other.
I must admit I've spent a little time pounding the keys trying to annihilate a co-worker or two in the past. A network is also a good way to allow more than one Mac access a single printer. Computers - Obviously the most significant part of any computer network are the computers. The first thing to look at is what kind of networking your Mac is capable of. You can take the time to pull out the manual that came with your Mac but you can also just pull it out and take a look at the back of your machine.