Passage 4 In 1939 two brothers, Mac and Dick McDonald, started a drive-in restaurant in San Bernadino, California. They carefully chose a busy corner for their location. They had run their own businesses for years, first a theater, then a barbecue（烤肉）restaurant, and then another drive-in. But in their new operation, they offered a new, shortened menu: French fries, hamburgers, and sodas. To this small selection they added one new concept: quick service, no waiters or waitresses, and no tips. Their hamburgers sold for fif cents. Cheese was another four cents. Their French fries and hamburgers had a remarkable uniformity, for the brothers had developed a strict routine for the preparation of their food, and they insisted on their cooks" sticking to their routine. Their new drive-in became incredibly popular, particularly for lunch. People drove up by the hundreds during the busy noontime. The self-service restaurant was so popular that the brothers had allowed ten copies of their restaurant to be opened. They were content with this modest success until they met Ray Kroc. Kroc was a salesman who met the McDonald brothers in 1954, when he was selling milk shake-mixing machines. He quickly saw the unique appeal of the brothers" fast-food restaurants and bought the right to franchise（特许经营）other copies of their restaurants. The agreement struck included the right to duplicate the menu. The equipment, even their red and white buildings with the golden arches（拱门）. Today McDonald’s is really a household name. Its names for its sandwiches have come to mean hamburger in the decades since the day Ray Kroc watched people rush up to order fif-cent hamburgers. In 1976, McDonald’s had over $ 1 billion in total sales. Its first twenty-two years is one of the most incredible success stories in modern American business history. This passage mainly talks about_______.