A ballroom or ballhall is a large room inside a building, the primary purpose of which is holding large formal parties called balls. Traditionally, most balls were held in private residences; many mansions contain one or more ballrooms. In other large houses, a large room such as the main drawing room, long gallery, or hall may double as a ballroom, but a good ballroom should have the right type of flooring, such as hardwood flooring or stone flooring. In later times the term ballroom has been used to describe nightclubs where customers dance, the Top Rank Suites in the United Kingdom for example were also often referred to as ballrooms. The phrase "having a ball" has grown to encompass many events where person are having fun, not just dancing.
Ballrooms are generally quite large, and may have ceilings higher than other rooms in the same building. The large amount of space for dancing, as well as the highly formal tone of events have given rise to ballroom dancing. The largest balls are now nearly always held in public buildings, and many hotels have a ballroom. They are also designed large to help the sound of orchestras carry well throughout the whole room.