Film noir is not easily defined. The actual words come from French and mean "black cinema." It was in France during the post-war years that the term was used to describe a certain set of Hollywood films that were saturated with a darkness and cynicism that was not seen before. These movies included The Maltese Falcon (1941), Double Indemnity (1944), Laura (1944), and Murder, My Sweet (1944).
One of the sub-genres that defined classic American crime and detective movies was film noir, a style that was pervasive in detective films of the 1940s and 1950s. Film noir arose during the post-World War II period in the United States as a generation that fought in one of the most brutal conflicts the world had ever seen returned home to a changed America where jobs were scarce and the national mood seemed darker and more cynical than during the war itself.