Panama City is the capital of Panama. Sitting on the Pacific end of the Panama canal it has long been a point of transit for travelers and freight and these days Tocumen Airport has become the busiest in Central America and one of Latin America's most important transfer hubs.
Panama City is a very multicultural place, with large populations from many different parts of the world. Spanish is spoken by most, and many speak some form of English. Customer service is slowly improving, and surprisingly dismal in hotels. However, on the streets, Panamanians are for the most part extremely friendly and helpful and would love to give you some advice.
There's great shopping, from high-end stores in the malls around Paitilla and in the banking district around Via España, to veritable bargains around La Central (Central Avenue, now turned into a pedestrian walkway) and the Los Pueblos outdoor mall. You can also find many ethnic stores (mostly Chinese and Indian), in certain parts of the city.