Web sites

Eliot Higgins is the founder of an online collective that picks apart conspiracy theories and investigates war crimes and hate crimes using clues from the Internet. His new book is We Are Bellingcat.

P.W. Singer and Emerson Brooking say social media has been manipulated to fuel popular uprisings and affect the course of military and political campaigns. Their new book is LikeWar.

The video-sharing Web site YouTube.com has changed the way some people see the Internet. But it's also changing how people hear vintage artists, from the late Wilson Pickett to the up-and-coming Arctic Monkeys.