Ladder

Vertical or steeply inclined set of rungs or steps

A ladder is a vertical or inclined set of rungs or steps commonly used for climbing or descending. There are two types: rigid ladders that are self-supporting or that may be leaned against a vertical surface such as a wall, and flexible ladders, such as those made of rope or wire rope, that may be hung from the top. The vertical members of a rigid ladder are called "stringers" or "rails" (US) or "stiles" (UK).

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