“Photojournalism is a particular form of journalism (the collecting, editing, and presenting of news material for publication or broadcast) that employs images in order to tell a news story.”
Photojournalism is separated by ethical idea behind the photos, in that they should be both honest and impartial whilst telling the story in strictly journalistic terms.
Photojournalism images have meaning to do with recent events. The situation implied by the images is usually fair and accurately represents the event(s) being shown. They are normally paired with other bits of information (a news article) to help make facts more relatable to the viewer.
When photojournalistic photos were originally printed in news papers, they were used more to enhance the text, rather than to be a medium of information. The first weekly newspaper to be illustrated with images was the Illustrated London News, which was first printed in 1842.