壁

A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or serves a decorative purpose. There are various types of walls, including border barriers between countries, brick walls, defensive walls in fortifications, and retaining walls that hold back dirt, stone, water, or noise. Walls can also be found in buildings, where they support roofs, floors, and ceilings, enclose spaces, and provide shelter and security.The construction of walls can be categorized into framed walls and mass-walls. Framed walls transfer the load to the foundation through posts, columns, or studs and typically consist of structural elements, insulation, and finish elements. Mass-walls are made of solid materials such as masonry, concrete, adobe, or rammed earth. Walls may also house utilities like electrical wiring or plumbing and must conform to local building and fire codes.Walls have historically served defensive purposes, and the term "wall" originally referred to defensive walls and ramparts. Examples of famous defensive walls include the Great Wall of China and Hadrian's Wall. Walls can also be used for decorative or aesthetic purposes.