1. Protagonist: The main character or hero of the play.
2. Antagonist: The villain or opposing character who creates conflict for the protagonist.
3. Supporting Characters: Secondary characters who play significant roles in the plot and support the main characters.
4. Extras: Minor characters with limited lines or non-speaking roles that add to the setting or atmosphere of the play.
It's important to note that the specific parts played by actors can vary widely depending on the play, its genre, and the playwright's intentions. Each play may have its own unique set of characters and roles that the actors portray.