A social networking service (also social networking site’, SNS or social media) is an online platform which people use to build social networks or social relations with other people who share similar personal or career interests, activities, backgrounds or real-life connections. Most social-network services are web-based and provide means for users to interact over the Internet, such as by e-mail, by instant messaging and through online forums. NSI is applying analogies and results from social networks design and analysis to communication networks.