Social Media and Networking are considered new technologies. Many get confused and mix them up or exchange as the same in many instances. Social Media exists as tools for social networks. The networks are the people within. The content generated by the networks is the media.
Terms are continuously redefined as new uses of the technologies emerge but think of social media as all of the content (pictures, videos, podcasts, comments, blog posts, etc.) produced by all the people in the network. In this instance the network isn't equipment but people. People in this instance are a community or those you meet if you showed up to a networking event to exchange business cards. The business cards and their stories are the social media content.