In-N-Out Burger started in 1948 in Baldwin Park, California, when Harry and Esther Snyder opened a tiny 10'x10' drive-thru stand, pioneering the use of a two-way speaker box for ordering without leaving your car, a revolutionary idea for post-war California, focusing on fresh, made-to-order burgers and a simple menu, a tradition continued by their granddaughter, Lynsi Snyder, who runs the family business today.