In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

Google has built its first self-driving car prototypes and hopes to test hundreds more models this summer. If all goes well, the company is planning a pilot program in California over the next few years.

Adele Clark, aged 8, looks at an animatronic Gallimimus dinosaur at the Natural History Museum on April 20, 2011 in London, England. The Age of the Dinosaur is a summer exhibition combining animatronic models, fossils and CGI film footage. (Photo by Matthew Lloyd/Getty Images)

A Porcupine on display during the PBS portion of the 2010 Summer TCA Press Tour at the Beverly Hilton Hotel on August 5, 2010 in Beverly Hills, California. (Photo by Frederick M. Brown/Getty Images)

American film director Mike Todd and his actress wife Elizabeth Taylor get into a spat after missing their flight from London to Nice on June 22, 1957. (Photo by AP Photo)

Dancers from the School of American Ballet Chloe Ellis (R) and Amarra Hong (L) prepare for a performance at the Queens Theatre in the Queens borough of New York February 28, 2016. (Photo by Shannon Stapleton/Reuters)

Children wave Vietnamese and American flags while waiting for arrival of U.S. President Barack Obama (not pictured) before a welcoming ceremony at the Presidential Palace in Hanoi, Vietnam May 23, 2016. (Photo by Reuters/Kham)

African migrants stranded in Costa Rica walk near garbage on the Inter-American highway at the border between Costa Rica and Nicaragua, in Penas Blancas, Costa Rica, September 8, 2016. (Photo by Juan Carlos Ulate/Reuters)