excerpts from wikipedia.com

A social network is a social structure made of nodes which are generally individuals or organizations. It indicates the ways in which they are connected through various social familiarities ranging from casual acquaintance to close familial bonds.The term was first coined in 1954 by J. A. Barnes.

Social networks connect people with all different types of interests, and one area that is expanding in the use of these networks is the corporate environment. Businesses are beginning to use social networks as a means of connecting employees and helping them to build profiles.

This makes them search able and be connected to other business professionals.

One example of a business social network is LinkedIn, a network that connects businesses by industry, functions, geography and areas of interest. Networks are usually free for businesses or at a low cost; this is very beneficial for entrepreneurs and small businesses looking to expand their contact base. These networks act as a customer relationship management tool for companies selling products and services.

Companies can also use social networks for advertising in the form of banners and text ads. Since businesses are expanding globally, social networks make it easier to keep in touch with other contacts around the world.

In general, social networking services, such as MySpace and Facebook, allow users to create a profile for themselves. Users can upload a picture of themselves and can often be “friends” with other users.

In most social networking services, both users must confirm that they are friends before they are linked. For example, if Alice lists Bob as a friend, then Bob would have to approve Alice’s friend request before they are listed as friends.

Some social networking sites have a “favorites” feature that do not need approval from the other user. Social networks usually have privacy controls that allow the users to choose who can view their profile or contact them, etc.