It is to attempt to reproduce the surface of reality with a minimum distortion, so directors of realistic films capture the spontaneity of events as they were viewed in real life. Basically, realistic directors aim for making an audience feel like being in the scene. For example, the Lumière brothers, who made The Arrival of a Train in France in 1869, were the pioneers of this style as well as filmmaking in general. Realism maybe an objective mirror of the actual world.
It is to change and stylize reality or create their own reality on a film. In other words, formalistic directors tend to express their subjective insights. For example, A Trip to the Moon(1902), which Georges Melies directed, was a typical mixture of whimsical narrative and trick photography. Expressionist, which is sometimes used as a synonym of formalism, tend to think their self-expression is at least as important as the subject matter itself. I think one of the most famous expressionism directors today is Tim Burton, who directed Alice in the world, Batman, Big Fish and Edward Scissorhands. In this kind of films, the camera is used as a method of commenting on the subject matter, a way of emphasizing it essential rather than its objective nature.
Also, the most extreme kind of the style of filmmaking is avant-garde cinema. They’re very abstract and made of pure forms such as nonpresentational colors, lines, and shapes. Maya Deren and Alexander Hammid’s Meshes of The Afternoon is one of many examples of this.
Gold Diggers of 1933 is known for the choreographies of Busby Berkely. It is far removed from the real world where there were depression-weary audiences. He liberalized the camera form narrow confines of the proscenium arch, soaring overhead, even swirling among the dancers, and juxtaposing shots from a variety of points throughout the musical numbers. He often photographed his dancers from unusual angles, like bird’s-eyeshot.