LinkedIn (LNKD) is a American social networking company whose main focus is connecting business professionals with each other, a sort of virtual Rolodex of business contacts and friends in your professional social network. The company was founded in December of 2002 and the site launched in May 2003. It was founded by Reid Hoffman and a group of founders from PayPal and As of 2011 the company boasted 135 million registered users in 200 countries and territories; handling the traffic of nearly 34 million unique visitors each month. LinkedIn stock went public in an IPO on May 19th, 2011.

With annual revenue of $243 million in 2010 and net income of $15 million LinkedIn generates most of its revenue through advertising on the site. In 2011 the company boasted of having more advertising revenue than ($155 million vs. $139.5 million). Its current areas of high growth are in India as well as having crossed 4 million users in the UK, 1 million in Spain and 1 million in Pakistan.\r\n\r\nThe basic idea behind LinkedIn is to aggregate one’s professional and personal contacts by degree of association. There are forums to join like-minded professionals to discuss their niche of the business world. It has also become a very important part of the job search; a place for recruiters and talent to meet and share information. There are over 870,000 groups on LinkedIn which can very quickly devolve into a means by which to e-mail spam a person’s in-box.

In 2008 the company added the ability to link up with apps to use their LinkedIn page as a home for cross-posting their blogs, current reading lists and the like. Users can now, as of July 2011, directly apply for jobs through LinkedIn, on job listing pages using their LinkedIn profile as their resume.

With the acquisition of Cardmunch, their mobile site will be able to scan business cards. The mobile site, after a revamp in 2011, has seen traffic increase over 400%, over time this should help LinkedIn’s stock price.