pro·logue 
/ˈproʊˌlɑ:g/ noun
plural pro·logues /ˈproʊˌlɑ:g/ noun [count] : an introduction to a book, play, etc.
▪ a brief, one-page prologue ▪ the prologue to his autobiography — often used figuratively ▪ events that were a prologue to war [=events that came before and led to war] — compare epilogue
▪ a brief, one-page prologue ▪ the prologue to his autobiography — often used figuratively ▪ events that were a prologue to war [=events that came before and led to war] — compare epilogue
