It's tough out there. Ask anyone looking for a job in nearly any field, and they'll be able to recite a long list of challenges that job-seekers face on a daily basis. Companies are closing or suspending hiring for the foreseeable future, competition for open positions has never been fiercer and the outlook for the nation's economy hasn't been this bleak in generations. Now, more than ever, job hunters need to be resourceful in their efforts to secure gainful employment, and few resources of late have proven to be more useful than social and professional networking sites.

It's certainly not difficult to understand why social and professional networking websites have exploded in popularity in recent years. They capitalize on the intrinsic human need to interact with and gain feedback from other people. Blogs, message boards and other online communities allow us to share ideas with people all over the world in real time and offer almost all the dynamics of human interaction.  How do these sites create opportunities for people to find work? Here are but a few ways they accomplish this:

• Connections, Connections, Connections - Whether you're looking for an entry-level job right out of college or a position in top management, the importance of having a connection to help you get noticed (and get an interview) cannot be overstated. Many people belong to several online networking communities, and making it known that you're looking for a new job allows you to tap into your extended network as well as the networks of others.

• Niche-Oriented Job Sites and Communities - More and more job and message boards are appearing online that cater to a very narrow range of interests and backgrounds, which enables job seekers to bypass huge, sprawling sites such as Monster.com where their résumés might be overlooked. For example, if you are Asian, a minority woman or a job-seeker with very specialized skills like forensic accounting, chances are very good that there are job boards online where you can get noticed that cater to these fields and demographics.

• Recruiters and Web-Savvy HR Directors Use Them Too! - Here's a very telling statistic on the relevance of social networking for job seekers: According to a 2006 study conducted by the Society for Human Resource Management, recruiters use social networking sites 23 percent more than they did in 2006 to verify resumes, screen applicants and fill vacancies.

• Reputation Management - Social media sites can be a boon or a bane. Since recruiters and HR directors are surfing social networking sites to gather information on prospective hires, job seekers need to be extra wary of unflattering images and information on their pages that could affect their chances of getting hired. Pictures of them engaging in illegal activity or posts they have made that denigrate former employers could come back to haunt them.

The Internet has significantly changed how people look for work and how prospective employers find qualified talent. Harnessing the power of social networking sites has become almost imperative for job hunters, but they need to be careful about how they might be perceived. Just like the community where you live, your connections will play a huge part in the speed and ease with which you can find a new position. However, just like an interview, you'll need to take extra care what kind of image you're projecting online.