By using a flashback, a writer can insert past events into the narrative in order to provide further context. the four main ways to employ a flashback are:

In literature, a flashback is an event in which a character remembers an earlier event that happened before the current point in time of the story.

Types of flashbacks are:

An external analepsis, which narrates an event that occurred before the story started. An internal analepsis, which narrates an event which has previously occurred in the story.A characterization flashback, which is used to narrate an elaborated story of the past as well as give background about a certain character in the story. A flash-forward, which is basically considered the whole story to be a flashback that will eventually bring the reader to present time once the story is reaching its end.