My favorite book on writing has always been Strunk and White's Elements of Style. They lay it out for you simply and directly, and they do not go on. You feel confident when you read that book; you don't feel overwhelmed or discouraged. So I've tried to do that same thing for playwriting. I've laid it all out for you without going on.I have just one suggestion before you begin. If you're inclined to write a play, you might want to read this book quickly, write your play, then read it again more carefully. It is definitely not a good idea to make yourself nuts with requirements, then try to make your play fit them. Tell the damn story. Then let this book help you fix it.