What is the 'show bible'?

What is the 'show bible'?

A “show bible” lays out the characters, the kinds of stories to be told and sometimes summarizes stories that have been told, as well as the needs of the show for the future. At one time, executive producers of shows would write “bibles” so that directors and outside writers coming in would understand the history of the stories and not accidentally repeat them, and also be able to fulfill the future needs of the show. Now, in place of “bibles”, most TV shows have websites that give all of that information.