A revolving door is a type of architectural door that rotates around a central axis and allows people to enter and leave a building without interfering with one another. There are several other words that can be used to describe revolving doors, such as turnstile, rotating door, carousel door, and circular door. Turnstiles are often used for high-security areas, such as airports and stadiums. The rotating door is commonly used in hotels, shopping malls, and office buildings. A carousel door typically has large glass panels that allow natural light into the building. A circular door is another type of revolving door that rotates horizontally instead of vertically. Regardless of the name, revolving doors are an efficient and stylish way to control access to a building while preserving its energy efficiency.