An office building is a structure that houses multiple businesses, organizations or professionals who share the same space for conducting their work. These buildings can range in size and style from small, one-story structures to large, multi-story skyscrapers. Office spaces within these buildings are typically leased out to tenants, who then design and furnish them according to their specific needs. Common amenities found in office buildings include conference rooms, break areas, restrooms, and elevators. The phrase "office building" can also refer to a particular type of real estate investment that generates rental income from the leasing of office space within the structure.