(Read more: Richard Branson on How to Leverage Social Media)
LinkedIn defined small-business professionals as people, who work at a company that employs between 11 to 500 workers. About 15.2 million site members—or about 8.7 percent of the site's 175 million members worldwide—are small-business professionals. Their occupations range from accessories designer to yacht broker.
"Given the global recession and the focus on small businesses in the U.S. presidential campaigns, we thought it would be interesting to find out how many small business professionals there are on LinkedIn," says Nicole Williams, LinkedIn's connection director.
Entrepreneurs use LinkedIn to conduct research, hold mini conferences, promote their companies and find mentors. Small-business professionals also turn to site networks to locate vendors, partners and investors in their companies. (Read more: Why Young Workers Prefer Start-Ups)
Adam Lewis, chief executive of Connecticut-based Pythio—which helps businesses collect data from business devices and other physical assets—says he's been a long time fan of the social media site and says it's helped him connect with industry leaders and potential new clients. The site also keeps him on top of sector trends.
"The traditional cocktails, network events aren't very effective," says Lewis.
There's also the trust factor that online communities offer, Lewis adds. LinkedIn allows users to see and learn from professionals in their respective fields—even if those individuals are strangers. For example, if a stranger's professional contacts include people you know and admire, chances are you'll trust that stranger's opinion on professional matters, Lewis explains.
Other popular social media tools include Twitter, Facebook and Google+ .
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