The term 'Doors' can be summarized as a type of portal. Doors are typically used to provide access to a building or room, and are usually made of wood, metal, or glass. They can also be used to provide security, privacy, and insulation. Doors can come in many different shapes and sizes, and can be opened manually or electronically. Doors are an essential part of any building, and are often the first thing people see when entering a space.