It is one of the shortest golf books out there, but the lessons in it are priceless classics. Harvey Penick was the long time teacher of Ben Crenshaw and Tom Kite, and gives advice from a golf instructor’s point of view. I believe the book contains around 90 lessons from Penick’s years of teaching. If you want to learn from one of the greatest swing instructors in history, this is your book.
I haven’t ever read the book straight through, but I like to jump around. I use it on a day by day basis. For example, I reference one of the lessons, and work on it for that day or longer. It is a great little reference book which will keep your game sharp.