Social computing and networking is concerned with the intersection of social behaviour and computing systems, creating or recreating social conventions and contexts through the use of software and technology. Various social computing applications such as blogs, email, instant messaging, social networking (Facebook, Twitter, LinkedIn, Google+ etc.), wikis, and social bookmarking have been widely popularised by providing digital platforms for social interaction. Such applications have been profoundly change social behaviours and digital life styles of humankind whilst pushing the boundaries of Internet technologies. While people can enjoy or even indulge in the benefits such as freedom and convenience brought about by social computing, various critical issues such as trust, privacy, HCI design, and the modelling as well as understanding of social behaviours via computational means provide significant challenges.