Social Computing a new paradigm is causing transformational changes to societal and business processes resulting in new businesses models known as sharing economy, peer economy or collaborative consumption. The diffusion rates of these applications have surpassed any historical technological advancement and have reached millions and billions of users during a short period of time. To understand this phenomenon we analysed eight such popular applications using inductive and content analysis techniques which have helped us derive a structural and a behavioural model for Social Computing. Using these two models we were able to get a deeper understanding of how an application designed to assist a particular communication pattern give rise to a set of emergent characteristics within the user such as trust, empowerment, belongingness that motivate user to act to fulfil a need assisting the growth of these applications. This understanding can guide the design of new successful Social Computing applications.