Social networking sites like Facebook are still mostly thought of as a toy for the younger generations. But HR pros using the sites to recruit employees will find a lot more than just college students and recent graduates.

The fastest growing population on Facebook: professional adults, according to O’Reilly Media.

Since September 2008, the number of Facebook users between the ages of 35 and 44 went up by 51%. Users age 45-54 increased by 47%, and by 26% for those 26-34.

Many of those users are logging on specifically for job-seeking purposes. As the site begins to attract huge numbers of people from all generations, it could be a great resource for HR and recruiting pros.

Tags: Facebook, social networking