What are the pros and cons of social networking sites?

Social networking sites like Facebook can be both useful and dangerous. See more pictures of popular web sites.
AP Photo/Paul Sakuma

Are you an online network socialite? Do you Twitter about your Facebook status while listening to music on Last.fm? Have your friends noticed that you'll only talk to them 140 characters at a time? Then you've got your finger on the pulse of online social networking -- a big part of Web 2.0.

Just a few years ago, the idea of an online social network was revolutionary. While the Web has always provided a way for people to make connections with one another, social networking sites made it easier than ever to find old friends and make new ones. Today, it's rare to find someone who hasn't at least heard of Facebook, MySpace, Twitter or one of a hundred other social networks.

For novices in the world of social networking, the vast online landscape can be a little intimidating. There are so many options available and each one has its own terms of service or end user license agreement (EULA). Even Web veterans may find some of these agreements difficult to understand. There are times when it can feel like you're signing your life away just to get a profile on a Web site. You may not even know why you would want to use such a site in the first place, apart from the fact that everyone else seems to be on it.

We've taken on the task to break down the positive and negative aspects of online social networking sites. Before we go much farther, understand that there are a lot of things you should take into consideration before signing up. You should also know that the good tends to outweigh the bad, particularly if you're careful about the way you use these sites. So, let's start off with the pros of social networking sites.