A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length.
A wooden fence
During the Cold War, West German trains ran through East Germany. This 1977 view shows how East German authorities placed fences near the tracks to keep potential defectors at bay
Typical agricultural barbed wire fencing
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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
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)
Wall art in Budapest's Széll Kálmán Square.
Glass curtain walls on a contemporary German skyscraper
Mirrored glass partition wall
Demountable wall and door in an office building