Chiaroscuro is an Italian term used to describe the technique of using light and dark in artwork, particularly paintings. It originally comes from the days of the Renaissance, and combines the Italian words: “chiaro” meaning “clear” or “bright,” and “oscuro” meaning “obscure” or “dark.” It refers to the dramatic effect experienced when using contrasting areas of light and dark in a piece.
In cinematography, the term refers to the extremes of low and high-contrast lighting to create areas of light and darkness in films. This applies especially to black and white films. Often the light would only illuminate half of the subject’s face, while obscuring the other side, giving them a three-dimensional shape and volume. Hollywood Film Noir made this their standard, though it came well before the 40s and 50s.