What is a social networking site? In non-techy English, it is a web site that leverages the exponential power of connections meaning that it provides you with tools to take advantage of the "who you know" network.
If you know 10 people, and they each know 10 people, the theory of social networking sites is that you now potentially know at least 100 people because your friends could introduce you to their friends. Another theory of social networking sites is that if you have things in common with your 10 friends, chances are you may have something in common with some of their 10 friends or some of those 100 other people. Most social networking sites are based around common interests as the magnet and the glue of "friendships."
The best way to understand how a social networking site works is to use one, but other than that, taking a look at the popular social networking sites can help. Here are some of the better-known social networking sites and the ones that are most focused on business networking
General Interest Social Networks
1. MySpace - This is the King of Social Networking sites but hasn't proven too useful for me professionally. It is sometimes more like a popularity contest but if you like music, movies, books and other entertainment, you'll find connections. My MySpace page: http://www.myspace.com/mediaegg
2. Facebook - What started out as a college social network has opened up to the masses and become very popular among professionals as well. I'm too busy playing Scrabulous (fun online Scrabble game with a Facebook version) to take full advantage of it, but am getting some professional networking done over multiple Scrabble games, believe it or not. My Facebook page: http://www.facebook.com/profile.php?id=562805152
3. Friendster - This used to be the frontrunner in the social networking site race but plummeted once MySpace took off (and now Facebook). But some people still take their Friendster pages seriously. I have made a few contacts, but nothing professionally fruitful. My Friendster page: http://profiles.friendster.com/alizasherman
Professional Social Networks
1. LinkedIn - This is really the top professional social networking site. Once you add your professional contacts, the site provides tools for getting introductions using the theory of 6 degrees of separation although usually anyone you'd like to meet is about 3 degrees away from you. I've made contact with former colleagues and have been able to get introductions to people I've wanted to meet such as an editor at LifetimeTV.com. My LinkedIn: http://www.linkedin.com/in/mediaegg
2. Ryze - This site hasn't been very useful for me, however, there is a strong Work at Home moms network within the site - http://WAHMs-network.ryze.com/. This is an example of how social networking sites allow people to create subgroups within the site utilizing all the networking tool that facilitate making contacts. My Ryze Page: http://www.ryze.com/go/alizasherman
3. Xing - If you are looking to make international contacts, this UK-based network has a global reach. My Xing Profile: https://www.xing.com/profile/Aliza_ShermanRisdahl
What can a social network do for your business? The main reason to join a social network is to make contacts and communicate with those contacts. From a business standpoint, a social networking site can make it easier for you to find the contacts you need.
For example, if you are looking for a good lawyer or accountant, someone in your network may know of someone – or know someone who knows of someone. It is faster and easier to send out one email to your entire network that they can easily pass along than to call people individually or email them all.
With a social networking site, you can see the contacts for all of your contacts and ask for an introduction. You might see that someone you know is connected to someone who is connected to a fantastic graphic designer. Instead of contacting that designer cold, you can have a personal introduction through the chain of contacts. Anyone in business knows that warm leads and referrals are far more trustworthy and productive than cold calls.
If you were to try only one social network as a businessperson, you probably should try LinkedIn. The site started as a place for professionals to connect and remains focused on business. There are no entertainment tools and applications on the site to distract you from the business at hand. They also offer a free account as well as a more feature-rich pro account.