According to Wikipedia, A social network is a social structure made up of individuals (or organizations) called "nodes", which are tied (connected) by one or more specific types of interdependency, such as friendship, kinship, common interest, financial exchange, dislike, sexual relationships, or relationships of beliefs, knowledge or prestige.
Social network connect one with each other person commonly by friendship or another social relationship. For a businessman, there is business social networking too.
The existence of social networking sites had drawn criticism for being less educated and cause addiction. Often people lose track of time in accessing social networking sites and can be alienated from real life. So, we as the users of social networking site, must be creative and smart so that we can get the advantages of this kind of networkin. We can use social networking site to spread business networking social, for example.
With the rise of Internet usage and the amount of interest in social networking sites, it can be best utilized. We can combine social networking and business for the progress of our efforts.