Mathew Brady’s 1860 photograph of Abraham Lincoln is likely the first truly mass-distributed image during a political campaign. Because it was reproduced in many forms—lithographs, wood engravings, etc.—it was widely visible, in periodicals and on campaign buttons, postcards, cartes de visite, and the like. Lincoln exclaimed that this photograph helped make him president, and the rest is history.

Mathew Brady / Library of Congress

Tabitha Soren, fine-art photographer

With the Untitled Film Stills series (1977–80), Cindy Sherman turned portraiture into performance: She fooled us by dressing herself up in different guises and then capturing her own image. Sherman also prefigured the idea that people are presenting a “self” all the time—even when not on camera and even without Instagram and Photoshop.

Reader Responses

Ernest Davis, New York, N.Y.

Rosalind Franklin and Raymond Gosling’s diffraction photographs of DNA (1952) were crucial to James Watson and Francis Crick’s discovery of its structure.

Henry Burney, Syosset, N.Y.

The photograph of the atomic cloud over Hiroshima introduced the world to the bomb’s destructive power and ushered in the nuclear arms race.

U.S. Army

Don Gervich, Watertown, Mass.

Nick Ut’s photograph of 9-year-old Phan Thị Kim Phúc—running, naked, and crying from napalm burns—captures war’s merciless cruelty. The 1972 image may have helped end the Vietnam conflict.

Nick Ut / AP

Brian G. Gilmore, Washington, D.C.

The photos of 14-year-old Emmett Till’s mutilated body that appeared in Jet magazine and other publications in 1955 energized the U.S. civil-rights movement. Rosa Parks later stated that what happened to Till was what made her decide to protest on the bus that day in Montgomery, Alabama.

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