Wikipedia on photojournalism

"Photojournalism is a particular form of journalism (the collecting, editing, and presenting of news material for publication or broadcast) that creates images in order to tell a news story. It is now usually understood to refer only to still images, and in some cases to video used in broadcast journalism. Photojournalism is distinguished from other close branches of photography (such as documentary photography, street photography or celebrity photography) by the qualities of:
Timeliness — the images have meaning in the context of a published chronological record of events.
Objectivity — the situation implied by the images is a fair and accurate representation of the events they depict.
Narrative — the images combine with other news elements, to inform and give insight to the viewer or reader.
Photojournalists must make decisions instantly and carry photographic equipment under the same circumstances as those involved in the subject (fire, war, rioting)—often while being exposed to the same risks.
Photojournalism as a descriptive term often implies the use of a certain bluntness of style or approach to image-making. The photojournalist approach to candid photography is becoming popular as a unique style of commercial photography. For example, many weddings today are shot in photojournalism style resulting in candid images that chronicle the events of the wedding day."