American President George W. Bush is officially sworn in for his second term. The launch of YouTube revolutionizes the way people consume and share video content online. The Mars Reconnaissance Orbiter is launched from Cape Canaveral. Roger Federer successfully defends his men’s singles title at Wimbledon while Venus Williams wins her third Wimbledon crown. For the first time since 1998, another second is added to end the year: 23:59:60.