A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or, is decorative. There are many kinds of walls, including:
* Walls in buildings that form a fundamental part of the superstructure or separate interior rooms, sometimes for fire safety
* Glass walls (a wall in which the primary structure is made of glass; does not include openings within walls that have glass coverings: these are windows)
* Border barriers between countries
* Brick walls
* Defensive walls in fortifications
* Permanent, solid fences
* Retaining walls, which hold back dirt, stone, water, or noise sound
* Stone walls
* Walls that protect from oceans (seawalls) or rivers (levees)