This thesis provides a conceptualization and evaluation of the different dimensions of viral marketing (i.e., good digital strategy, viral and mega viral), as well as an identification of what triggers consumers to share videos and other digital content made by and for brands. In addition, based off of the research and three case studies that exemplify viral marketing (i.e. Nike, Blendtec and Old Spice), this thesis provides an application of viral marketing to the brand JanSport.