If you're a business owner, have you considered the myriad of ways that social networking sites can help you in your hiring decisions? Given the number of individuals using social networks like Facebook, MySpace, and Twitter, it's almost foolish not to do a little digging on such sites when you're looking for prospective employees. In the past, many employers have entered prospective employees' names into search engines, but social networking sites are a whole different ballgame. They encourage users to post personal information and have broken down the barrier between what is kept private and what is shared with everyone.

CareerBuilder recently released survey results showing that 22% of the respondents check social networking sites when considering adding a prospective employee to the candidate pool. And almost one-third said that information they had found on social networking sites caused them to release employees from the pool of candidates. Respondents said that information most likely to influence them included alcohol and drug use, poor communication skills, negative information about coworkers and employers, and inappropriate photographs.

Twitter, the newest of the highly-popular social networking tools, also offers employers a way to obtain information about employees. Twitter displays the time and date of each post, giving employers invaluable information when they read that Employee X is “sneaking away for an hour” while he's supposed to be working on a project. Can you imagine how it will affect your hiring practices to know what your prospective employee has tweeted in the days and hours before her interview?

Social networking sites can play a huge part in your hiring practices. But what if you're the one looking for the job? Keep these 5 rules in mind:

1. Be Picky About Your Friends. No matter how clean you keep your comments and your profile, you may have friends who post those photos from last weekend when you couldn't even stand up straight. If you have friends whose discretion leaves much to be desired, at least request that they not provide compromising content about you.

2. Be as Professional as Possible. It's fine to chit-chat with friends on your profile as long as you keep it to a minimum and as long as your banter is innocuous. Be careful about everything you post.

3. Ponder the Details. Part of the fun of social networking sites is adding interesting applications and updating your status. But think about how a person who hardly knows you will interpret your applications and updates. If it's at all questionable, leave it off of your profile.

4. Use Your Time Wisely. If the social networking site you're using has a time stamp, current and potential employers can quickly see how long you're spending online. So minimize that time.

5. Check Regularly. You don't need to check your accounts every five minutes, but be aware of what's going on as much as possible. If a “friend” posts something embarrassing and you don't notice it until three days later, a potential employer might have already seen it and made a decision based upon it. Likewise, if you have older accounts that haven't been updated in awhile, delete them or update them. Potential employers should have the most up-to-date information possible.

Social networks are a great tool for getting “insider” information on potential employees, that information that you always wish you'd known before you made a hire. Don't hesitate to use it to your advantage and weed out candidates before you have a chance to waste your time interviewing them. And if you're really excited about positive information you find on a candidate's profile, use that to guide conversations once you actually have the chance to talk to them. Social networking is an invaluable tool, so use it