Modern photography began in 1839 when Louis Daguerre invented his eponymous daguerreotype. This image-making process could reproduce a fleeting image on on a metal plate in just 30 minutes. Since then, photography has gone through many developments, from 35mm film to digital imaging, and has had a significant impact on many aspects of society.
Photography changed the way we remember things. It offers instantaneity and has the ability to capture actual events, a slice of reality. Roland Barthes, a preeminent theorist of photography, said that photograph is the "sovereign contingency," meaning it is dependent on something else happening. We now look to photographs as confirmation of memory.
Photography has played a large role in our conception of history. Historically, photographs provided an objective record of real events. They were key, for instance, in confirming for the public the ravages of the Civil War and horrors of the Holocaust. However, we now know that photographic images can be manipulated.
A tangible impact of photography has been the number of people employed in the industry, particularly after the introduction of 35mm film in the 1920s by the Kodak company. The innovation meant a number of people were needed to sell and service cameras and films. Photography also meant new employment opportunities as photo reporters and editors, and in photographic agencies and libraries.
In its earliest incarnations, photography was still the domain of the rich. However, the Eastman Kodak company, which invented the instant camera and cheap 35mm film, put the power of photography in the hands of the general public. Anyone could point and click a camera, making photography the most widely used art form.
The ability of the camera to record the world as it is has made it an invaluable tool in scientific research. It its early days it was used to record evidence on field trips, show portraits of remote tribes people or newly discovered animal species. For example, Eadweard Muybridge's ability to shoot consecutive photographs in quick succession demonstrated that a horse has all four legs off the ground at certain points when running. Photographic technology has led directly to scientific innovation in brain scanning and assessment of the human body.
It could be argued that the invention of photography liberated the traditional arts (painting, sculpture, even literature) from the yoke of representation. Previously, art had been used to simply reproduce the world, but photography could do that better than any other form, and much more quickly. Artist had to find new modes of operation and seismic shifts in art production, from modernism to abstract expressionism, were all conceived in the wake of photography.