Definition
Flashbacks alter the story order so that the plot moves back to show events that have taken place earlier than the one already shown.
Purpose
The flashback can help inform the audience of a character's back story.
Details
Directors use a variety of techniques to distinguish the flashback from the present day. Some of these include; distinct change of setting, use of music or special effects on the film such as; black and white to show scenes that happened in the past.