What are the purposes of a prologue in a play

it tells the entire story so that the audience can in a way expect the tragic ending. And feel the circumstances of the play.

Explanation:

Sometimes it tells you what’s going to happen before it happens.

Sometimes a prologue tells you what is going to happen before it happens.

Explanation: A good example of this is the prologue of Romeo and Juliet, which lays out the story in large portions.

the characters in string all have major secrets that they strive to avoid revealing throughout the play.