LinkedIn.com is a social networking service aimed at career professionals and business-oriented individuals. With LinkedIn, you post your CV and professional associations to network with connections and business contacts.

LinkedIn was founded by Reid Hoffman and a team of individuals in 2002 and launched publicly in May 2003. Since then, it has grown to include over 75 million users in over 200 countries worldwide.

"We're always about individual professionals doing business with their network," said Hoffman, now a chair on the board of directors. "The philosophy behind LinkedIn has not changed. If anything, it's gotten bigger."

LinkedIn is the leading network of its type, one that stretches the title of "social" media. The site is a legitimate source of business and career opportunities. The company executes a lot of research and development to stay on top of trends and provide an online networking experience like no other company.

In August 2010, LinkedIn announced the acquisition of mSpoke, a startup based in Pittsburgh that makes search content more relevant by an adaptive, personalized recommendation system. Presumably, the idea of career networking and job-hunting could only stand to be improved by such a service.

How it works
Users create a profile for themselves, adding information relevant to their employment, education, and professional affiliations — it's a new way of having a resume online. From there, you invite colleagues with accounts into your professional network and interact with them for the sake of career networking.

LinkedIn can be used to search for jobs, track publications by individuals and groups that you deem to be important and promote professional recommendation by way of testimonials written and displayed on individuals' profiles. It is a barometer that indicates your professional social standing.

Why it's useful (or not)
LinkedIn is essentially the next level of professional networking. More direct and powerful than simple job search websites like Monster.ca or Workopolis.com, LinkedIn gives you the power to connect directly with other users or employers.

You can also opt into a paid version — the free service puts a limit to how you can make contacts, and how many you can make. The premium membership, composed of some one per cent of members, increases your member status and grants you the ability to reach out to certain members and users without being previously acquainted.

As a warning, it is perhaps most useful if you take it seriously enough to use it to its full potential. Leading professional experts advise that to get the most out of LinkedIn, you should complete your profile by filling in all information, integrate every professional connection (at least 100, some say), and be a visible member of the community by taking part in discussions and exchanging recommendations with your contacts.

With LinkedIn, the old adage, "It isn't what you know, it's who you know," could not be truer. It's more important than ever to update your profile to keep up with the times; LinkedIn will reward the ever-vigilant career-minded opportunist, and leave the stagnant far behind.