Gerald Bundy of Philadelphia was 13 when his older cousin convinced him to go to the March on Washington in 1963. Bundy returned 50 years later to celebrate the anniversary. When he looks back on it now he believes the experience, "made me more cognizant of social justice; made me an activist." Chloe Coleman/NPR hide caption

itoggle caption Chloe Coleman/NPR

A framed picture of Lily Ramos with her two girls at her home in Bend, Ore. She left the picture and her kids — Brian, Ashley and Karleen — with a relative when she was deported to Mexico. "No quiero que sufren," she said. "I don't want them to suffer." Dania Maxwell hide caption

itoggle caption Dania Maxwell

Cubs of the Simba East pride: too young to kill but old enough to crave meat. Adult females, and sometimes males, do the hunting. Zebras and wildebeests rank high as chosen prey in the rainy season. Michael Nichols/National Geographic hide caption

itoggle caption Michael Nichols/National Geographic

A major tributary of the Colorado River, the Dolores River Basin, is seen south of Grand Junction, Colo. Ken Neubecker, executive director of the Western Rivers Institute, talks about the connection of water and energy. "Water takes a lot of energy, a huge amount of energy; people don't realize it. We tend to take water for granted." Heather Rousseau hide caption

itoggle caption Heather Rousseau

An American soldier reads a letter from home, while taking a break from repairing a tank tread in Lang Vei, Vietnam, in March 1971. David Burnett/Contact Press Images hide caption

itoggle caption David Burnett/Contact Press Images

The Angolan exhibit consists of tall stacks of large photographic posters by artist Edson Chagas. The country, which is exhibiting at Venice for the first time, won the Golden Lion award for best national pavilion. Courtesy of www.beyondentrophy.com hide caption

itoggle caption Courtesy of www.beyondentrophy.com

In the future, a hard drive full of photographs may serve as the digital analog of a pile of old pictures. iStockphoto.com hide caption

itoggle caption iStockphoto.com