I'd suggest watching "The Social Network." I found it immensely interesting.
From what I could gather (others feel free to correct me or add), the dorms or houses on campus used to hand out actual paper books (called face books) which had the names and headshots of people, so that the people within the houses could know each other. Over time, some of them went digital, but they weren't networked together. Mark created a script that pulled in all the info from the various houses and created "The Face Book" as a singular entity. It was designed to be a networking site purely for Harvard students, and then later other universities.
Eh... you know how it is with the elite. They network within their own. Really successful people have powerful networks- they know who to call on when they're starting a venture or need help with something and they know who to call when they need money. At the onset of it, it was supposed to be an elitist social network, exclusive to the ivy leaguers, which is kind of brilliant on its own. The fact that less-than ivy leaguers are now spending hours a day killing brain cells with certain game apps... that part is a little spooky.
It was created for college students so maybe that helps explain it. In college books are part of it but the social aspect is equally important for many.
Just Asking 