The following series of stories detail some of what happened in 2003 and 2004 after then Harvard-sophomore Mark Zuckerberg launched a site called theFacebook.com. This site, of course, quickly grew into the dominant global site known as Facebook, which is now used by some 400 million people a month.

The stories are based on a long investigation into the origins of Facebook that included interviews with more than a dozen sources familiar with aspects of what happened, as well as what we believe to be relevant IMs and emails from the period. Much of the information has never been reported.

The stories detail some troubling behavior by Facebook's then 19-year old founder and CEO, Mark Zuckerberg, including using members' Facebook login information to break into members' private email accounts and hacking into a competitor's site and changing user profiles.

A source close to the company suggests that the fallout from this behavior has played a profound role in shaping Facebook's current privacy policies and Mark's current attitudes and conduct as a now 25-year old CEO. One can only hope so.