When we refer to Social Networks, a picture that comes to mind is a map with too many connections with people as nodes connected to each other via relationships. It isn't a mere set of people; it's a basis on which social media, social net work ing sites, millions of businesses work.
Social networks have power because they have a value. Some networks are more valuable than others which depend on the nodes, roles played by nodes, relationship between nodes and strength of relationships.
Facebook works as a social network because it has nodes (people) connected virtually via some relationships; it has immense value, hence power. Therefore marketers want to tap the potential of the powerful network. Same is with twitter, groupon, linkedin, etc
A group of friends, a group of relatives, and an organization is also a powerful social network; however internet has means to connect almost everyone to one group more easily (which is difficult physically); online networks become more powerful than offline.
Power of a network can be judged from the value to delivers to each node and to the environment.
A social network therefore may be called as a set of people which creates value from within and delivers to itself and society.
"TV and Radio" or broadcast era was like all nodes connected to one master node. The message is transferred to all nodes, no matter receivers can understand them or not with no questioning back to the master node. Broadcasting network has a power depending upon number of people at the receivers end. According to Sarnoff's law, a network is as powerful as the number of nodes. A network with 100 people is 10 times more popular than a network with 10 nodes.
This is another jargon given to a basic concept of people connecting to people. Example – everyone having a phone and anyone can call anyone. Having friends on facebook is another example of Metcalfe. It made life simpler and two way communications was possible. Here, a network of 100 is 100 times more powerful than a network of 10.
Value of network grows more powerfully when people of similar interests form a group. These groups can then connect with others and with individuals. Subscribing to interested fan pages on facebook is an example where people of similar interest come together and share views and feedback. This helps a community grow and help all nodes develop into more informed individuals.
Enough of theory, what is the use?
How powerful and how much value do you want your business to deliver. It is not always necessary to use the most efficient mode of communication, figure out which one is best for your customers / employees and bottom line.