Biography provided by Focal press
 
A painter influenced by surrealism purchased a 35 mm Leica camera in 1931, which led him to photograph the world and develop a street photography style called the "Decisive Moment" — "the simultaneous recognition, in a fraction of a second, of the significance of an event as well as a precise organization of forms which gave that event its proper expression." This watchfulness for peak moments, when the formal spatial relationships of the subjects reveal their essential meaning, defined and shaped the modernist, small-camera aesthetic of intuitively anticipating when an element of life opens for an instant and defines itself. His full-frame aesthetic, a scene completely visualized at the time of exposure, separated the mental act of seeing from the physical craft of photography. His stripped-down photographic grammar shunned fine print axioms in favor of a direct application of materials and process, which was ideal for photographers who traveled and made their living by having their work reproduced in magazines and newspapers. Co-founder with Robert Capa of the photographic cooperative Magnum (1947).
 
(Author: RH)
 
Michael Peres (Editor-in-Chief), 2007, Focal Encyclopedia of Photography, 4th edition, (Focal Press) [ISBN-10: 0240807405, ISBN-13: 978-0240807409] (Used with permission)
 
Wikipedia
 
Henri Cartier-Bresson (French: [kaʁtje bʁɛsɔ̃]; 22 August 1908 - 3 August 2004) was a French artist and humanist photographer considered a master of candid photography, and an early user of 35mm film. He pioneered the genre of street photography, and viewed photography as capturing a decisive moment. Cartier-Bresson was one of the founding members of Magnum Photos in 1947. In the 1970s, he largely discontinued his photographic work, instead opting to paint.