Use of Montage

Scorsese used montage to break up the narrative, and to provide more information about a character or events without using chronological narrative or even dialogue.
My favourite use of this was in Raging Bull, where a montage in colour separated the first half of the black and white film from the second.



There is also an amazing use of montage in Shutter Island, in Teddy's dream sequence. He sees himself back at Auschwitz, and elements of the present, such as the escaped prisoner he is supposed to be looking for, and her daughter, combine with the bodies that he saw at the concentration camp. He is then back on Shutter Island, and the prisoner and her daughter enter the room after a scream. Slow motion, reverse (of the smoke into his cigarette) and shots in time with the music all separate this scene from the reality of the film, emphasising that it is a dream sequence and also breaking up the narrative of the film - both future elements and elements of the past are addressed.
(from 1:30)