The document provides information about Shanghai, describing it as China's major eastern gateway to the world and largest seaport. It notes that Shanghai used to be divided by foreign concessions but is now an important center for economy, finance, trade, shipping, science, technology, information and culture. The summary concludes that Shanghai is a historic cultural city, the birthplace of the Communist Party of China, with a variety of architectural styles that have earned it a reputation as an exhibition of world architecture.