How Networks Work

Computers aren't people, but they still communicate on a network similar to how a group of people communicates. That is, computers send out information that is addressed to a particular individual and then wait for a response that tells them that the message was successfully received. PCs perform this task quickly, and that's part of what makes networks so practical.

To get a better understanding of the process, imagine that Sarah is working on a homework assignment on the PC in her room. When she completes her book report, she needs a printed copy, but she doesn't have a printer connected to her PC. A printer is connected to the PC in the den, and she can use it to print out her report. The conversation between the PCs goes something like this:

"Hello den computer, this is Sarah's PC. I'm sending you this report to print."
"Okay, Sarah's PC, this is the den PC. I received the data and sent it to my printer."

Sure, that exchange sounds trivial, but it does provide a nutshell description of what's going on. At a basic level, a network functions quite simply by sending different messages as needed. The information in those messages—the data—can be something like Sarah's book report,digital images from your recent vacation, music files that you've saved on one of your PCs, or whatever other types of information you want to share.

Things are more complicated inside the inner workings of the network. In Sarah's case, for example, the printer and the den PC actually engage in quite a bit of additional conversation, discussing whether the printer is out of paper, how many pages have finished printing so far, and details of what other reports the printer has been asked to print recently. Just like the telephone network, your computer network has to keep track of who is supposed to get each bit of information and make sure that everyone else isn't drowned by a sea of data that's not intended for them. Fortunately, your network automatically handles this additional complication, and you don't have to worry about it.