First question: The backstory gives the audience information about the events that occurred before the play began.
Second question: The main purpose of a backstory is to explain what has happened before the story.
Answer:
The details of characterization can help reveal things about characters. This is because when you anaylze their speech, thoughts, expressons, and physical appearance you can get personality traits and use the evidence that you collected from the STEAL method to reveal the character's personality.
