In 1948, the first In-N-Out Burger was founded by Harry and Esther Snyder in Baldwin Park. Harry's idea of a drive-thru hamburger stand where customers could order through a two-way speaker box was quite unique. In that era, it was common to see carhops serving those who wanted to order food from their car. Harry's idea caught on and California's first drive-thru hamburger stand was born.

The Snyder's business philosophy was simple: "Give customers the freshest, highest quality foods you can buy and provide them with friendly service in a sparkling clean environment." These principles have worked so well over the years that they are still the company's fundamental philosophy.