what is roof

A roof is the top covering of a building, including all materials and constructions necessary to support it on the walls of the building or on uprights, providing protection against rain, snow, sunlight, extremes of temperature, and wind. It is part of the building envelope and its characteristics depend on the purpose of the building, available roofing materials, local traditions of construction, and wider concepts of architectural design and practice. The shape of roofs differs greatly from region to region and is influenced by the climate and available materials for roof structure and the outer covering. There are various types of roofs, such as gable roofs, hip roofs, flat roofs, mansard roofs, and gambrel roofs, each with its own unique characteristics and functions