Audi, one of the world's successful car brands, is an international luxurious car brand representing high-tech, quality standards, capacity to create, and classic car style. The company is based in ingorstadt, germany. The odi group includes the parent company and its subsidiaries, odi hungary, quartro ltd., lamborgini motors and cosworth technology, odi brazil and odisenarita. In addition, audi has production plants in china, malaysia and south africa. Audi is one of the oldest car manufacturers in germany. Since 1932, audi has introduced the four ring logo, which symbolizes the automotive union company, which combines audi and miracles (dkw), horch and wanderer. In the 1930s, automotive union companies covered all areas of passenger cars that the german automobile industry could provide, from motorcycles to luxury cars. The audi sedan is marked by four circles representing the four companies before the merger. These companies used to be producers of bicycles, motorcycles and minibuses. Since the company was originally formed by the merger of four companies, each ring is a symbol of one of the companies. From 1933 to 1939, the audi automobile union grew rapidly: sales rose steadily from dm 65 million to dm 276 million; employees increased from 8,000 to more than 23,000; annual motorcycle production increased from 12,000 to 59,000; and annual car production increased from 17,000 to 67,000. The automobiles of the union of automobiles have acquired more than 3,000 patents in germany and elsewhere, thus demonstrating their ability to create them. In 1938, a quarter of passenger car orders were made by the automobile union and a third of motorcycle orders were made by dkw. It is thanks to its numerous technological advances, research findings and ideas that the automobile union has played a leading role in the creation of modern cars。