A double decker bus is a large bus that has two levels or decks for passengers. The lower deck is the main entry area with seating, while the upper deck provides additional seats and a higher view of the surroundings. This design allows the bus to carry more passengers compared to a regular single-deck bus. Double decker buses are commonly used in big cities and popular tourist destinations because they can transport many people at the same time. They are also widely used for sightseeing tours, allowing passengers on the top deck to enjoy a better view of the city, landmarks, and attractions. These buses are designed with safety and comfort in mind. They usually include comfortable seats, strong railings, wide staircases connecting the two decks, and sometimes air-conditioning and large windows for better visibility. Some modern double decker buses also provide audio guides and open-top seating for tourists. Overall, double decker buses are an efficient and unique mode of transportation. They offer higher passenger capacity, better views for sightseeing, and a memorable travel experience for passengers.