History of Professional Networking

I am working on a chapter about professional networking for the 5th edition of the Nursing and Informatics textbook.  The historical development of social media and networking is fascinating.  I enjoy reading posts on Twitter and Facebook.  The shared information helps me to feel connected to what is important. A video cartoon from Time.com is below.  A very nice infographic on the history is at http://www.creativeramblings.com/social-media-history-infographic-updated/
(It has code for embedding, but I could not get the code to work)