Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.

LONDON, ENGLAND - MARCH 25:  In this photo illustration the Social networking site Facebook is displayed on a laptop screen on March 25, 2009 in London, England. The British government has made proposals which would force Social networking websites such as Facebook to pass on details of users, friends and contacts to help fight terrorism.  (Photo by Dan Kitwood/Getty Images)
LONDON, ENGLAND - MARCH 25:  In this photo illustration the Social networking site Facebook is displayed on a laptop screen on March 25, 2009 in London, England. The British government has made proposals which would force Social networking websites such as Facebook to pass on details of users, friends and contacts to help fight terrorism.  (Photo by Dan Kitwood/Getty Images)

    JUST WATCHED

    Facebook experiment rankles users

MUST WATCH

Facebook experiment rankles users

NYU professor Lauren Walsh and author Ben Mezrich discuss revelations about Facebook's secret studies on user behavior.

Facebook experiment rankles users

NYU professor Lauren Walsh and author Ben Mezrich discuss revelations about Facebook's secret studies on user behavior.