How McDonald's got its start as a barbecue restaurant in the 1940s

• The first McDonald's restaurant, opened in 1940, was a barbecue restaurant that sold hot dogs.
• In 1948, the McDonald brothers switched the concept to become a burger restaurant.
• In 1961, Ray Kroc bought out the McDonald brothers and began to transform the chain into a global franchise.

The first McDonald's restaurant, before it became the chain it is today, wasn't primarily a burger restaurant. It was a barbecue joint. 

The very first McDonald's Bar-B-Q was opened on May 15, 1940, in San Bernardino, California, by brothers Richard and Maurice "Mac" McDonald. They moved from New Hampshire to open their own drive-in restaurant to cater to the hustle and bustle of the Hollywood lifestyle.

Car-hops delivered food to guests waiting in their vehicles, and the business was largely successful. According to a blog posted by the Library of Congress, the brothers' annual sales topped $200,000 on a regular basis. 

The drive-in's menu was large and its most famous offering was hot dogs.

In 1948, the McDonald brothers switched the concept to become a burger restaurant and reduced the restaurant's offerings to just 9 items

The restaurant now sold hamburgers, cheeseburgers, soft drinks, milk, coffee, potato chips, and a slice of pie.

In 1948, the McDonald brothers lowered the cost of their burgers to just 15 cents, roughly half the price of local competitors. In 1949, potato chips were swapped for french fries and McDonald's began selling milkshakes.

Due to the restaurant's self-service counter, known as the Speedee Service System, there was no need for waiters or waitresses. Burgers were cooked ahead of time, wrapped in paper, and kept warm under a heat lamp, which meant customers received their food in record time.

In 1954, future McDonald's Corporation founder Ray Kroc, a Multimixer-milkshake-machine salesman, came across the small burger joint. Amazed by its efficiency, Kroc wanted in. He became the first McDonald's franchise agent.

Ray Kroc opened the first McDonald's franchise location in Des Plaines, Illinois, on April 15, 1955

According to McDonald's, first-day sales at the new location were $366.12.

In 1955, Kroc founded McDonald's System, Inc., which would become the McDonald's Corporation we know today. By 1958, McDonald's had sold 100 million burgers.

In 1961, Kroc bought the McDonald brothers out for $2.7 million. He now owned the exclusive brand name rights and operation of all McDonald's locations, and would work to build the franchise into the global fast-food superpower we know today.