Let’s try the difference between these four different things: the stairs, ladder, steps, and stepladder. These may be divided into two sets of classifications, depending on whether they are moveable or fixed. The ladder and stepladder are moveable equipment, while the stairs and steps are fixed to the building.
A ladder has a series of rungs between two upright wood or metals and is always leaned against a wall or a flat surface in order for it to be used. It is portable.
The step ladder consists of two ladders that are hinged at the tip. It can support itself without being leaned to a wall or a surface. It is also moveable.
The stairs, on the other hand, are sets of steps from one floor to another inside a building. It is fixed and cannot be moved. It usually has a handrail and banister.
Lastly, steps are a series of steps that are outside of the building. It can be small or a large number outside the building made of concrete or stone.
Rule of thumb: Stairs are fixed steps inside a building, Steps are fixed steps outside the building. Ladders are movable steps that are leaned to a wall while stepladders are movable ladders hinged together at one point requiring no external support.
References:
“Ladder vs. Stairs”. https://www.vocabulary.cl/english/ladder-stepladder-stairs-steps.htm#:~:text=In%20general%2C%20a%20ladder%20and,are%20in%20a%20fixed%20position.
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