Stacy Perman is the author of In-N-Out Burger: A Behind-the-Counter Look at the Fast-Food Chain That Breaks All the Rules.
The first In-N-Out Burger was opened in Baldwin Park in 1948 by Harry and Esther Snyder. It was the first restaurant to use a two-way speaker box so that customers could order from their cars. In-N-Out is still run by the Snyder family and they have no plans to take the company public.
The "official" secret (or not-so-secret) menu can be found here.
This unofficial menu includes Animal Style Fries, a Neopolitan Shake and the Flying Dutchman.
Music Break: Work Song by Alan Randall