Screenwriting Texts discussion

What is your favorite screenwriting book? Is it a text book? Or some other kind of book?

My favorite book about screenwriting is Paul Lucey's Story Sense. It's a great book that shows readers all of the components of screenplays and screenwriting. I've used it as a reference tool to write two screenplays. I've read it several times. It's great.

I'm currently reading the Backstory series of books about Hollywood Screenwriters by Patrick McGilligan. So the first book in the series is great. It's astounding to learn about Screenwriters who had three or even four credits for screenplays in one year. That was back in the Golden Age. Before TV. Could you imagine life without TV? I'm looking forward to the next book in the series.