A survey by the Ponemon institute found 25% of employers are using these sites as a background check. In about 30% of cases they claim what they've found effected their decision.
18-year-old Melanie Young has both a MySpace and a Facebook page. "I have friends everywhere. I like keeping in touch with them," she says.
That's why the Dallas college student uses the social networking sites to share stories and pictures.
But Melanie's friends might not be the only ones surfing her site.
Dallas-based Ryan and Company admits they've used these sites before to screen job applicants.
"When an individual gets to that point where they're looking for a position they need to realize that facebook becomes an extension of your resume," claims Chief HR Officer Delta Emerson of Ryan and Company.
Attorney Clint David says, "A lot of things that people are putting up on their site ranks way up on the stupid meter."
David says employers searching these sites may be a common practice, but it's a risky one.
"You will have access to information on somebody's webpage that is very personal things like religion, sexual orientation, a medical condition. If you do not hire that person, they can come and say that you didn't hire Ihem because of those reasons."
And while he suggests employers use caution, Melanie Young says she plans to do the same. "Obviously the ones with me drinking or not being so conservative, are the ones I probably would take down."
While both MySpace and Facebook have privacy settings, employers say that doesn't necessarily keep people you don't want on your site off of it.