The word '''atrium''' is a Latin architectural term that referred to an open courtyard, that is without a roof, in large Roman houses from which are extended the enclosed rooms of the house (‘‘domus’‘). A shallow pool, impluvium in Latin, may be sunken in the floor of the atrium. In modern usage, atrium is used to describe a large open space, often several stories high, in large, mainly office, buildings that provide a feeling of space and light.