On January 9th, LinkedIn, a social networking site for business professionals, announced crossing the 200 million member mark. While this is a definite milestone for the company, it doesn’t come as a surprise to anyone following the company closely. Since founded in 2003, LinkedIn has grown exponentially to become the the world’s largest online professional network. The membership isn’t exclusive to the western part of the world, either. Even though the United States makes up for almost half of LinkedIn’s members, LinkedIn is available in 19 languages and has users in over 200 countries.

What makes LinkedIn different from other large social networks? Take Facebook for instance. As of October 2012, Facebook had one billion users. These users, however, are hardly a niche group. Facebook is a great place to market an existing business, but not an ideal spot for professional networking. The intent of Facebook users can vary just as much as the users themselves and users often try to separate their professional lives from their personal lives on Facebook.

Though not as big as Facebook, Twitter is another large player in the social media marketing scene. The micro-blogging platform Twitter eclipsed the 500 million user mark in April of 2012 and shows no signs of slowing down. Again, the users don’t share a similar goal or objective. Some may be interested in promoting their business and others may be focused on celebrities. The various interests of the audience on Twitter makes it a difficult place for a networking business professional to navigate.

Two relatively new social networks, Instagram and Pinterest are each unique and useful in their own right as well, but are additions to the personal side of social networking. This is where LinkedIn breaks the mold. LinkedIn isn’t just another social network for personal use. LinkedIn is social media you use for work and at work. Instead of disconnecting themselves from their jobs, LinkedIn users rely on that information to grow their networks.

LinkedIn carries many of the same features as other social media sites like connecting with specific people, sharing articles and forming groups, but unlike the other top social networks, LinkedIn is specifically catered to a professional crowd. Users of LinkedIn connect and network with one another via professional relationships and can also connect with specific businesses. The networking aspect is taken a step further when a user can see which members of their own network may be able to connect them with a prospective customer or employer.

LinkedIn’s explosive growth has cemented its place as the choice for professionals looking to network online. The homogeneous goals of the user-base, coupled with fantastic corporate management, will ensure LinkedIn’s success does not stop at 200 million.