In the past, individuals could take a career test and then spend time preparing for an in-person job interview in the hopes that their charm, charisma and intelligence would leave employers with a very good first impression. These days, social media is making it harder for candidates to prevent companies from forming their own first impressions based on the information candidates have on their Facebook or LinkedIn profiles.

CareerBuilder recently revealed that 37 percent of companies visit social networking platforms to research job candidates. The career website commissioned a survey of 2,303 hiring managers and human resource professionals to find out what role social media plays in shaping employers' opinions of potential workers.

Roughly 65 percent of survey respondents use social media to see how professionally candidates present themselves, 51 percent try to figure out if applicants would make a good fit and 45 percent have an interest in qualifications.

"Because social media is a dominant form of communication today, you can certainly learn a lot about a person by viewing their public, online personas," said Rosemary Haefner, CareerBuilder's vice president of human resources.