* It's a concept: The sky is our perception of the atmosphere, the layer of gases surrounding the Earth. It's a visual effect created by light scattering and reflection.
* It's not a solid object: You can't touch the sky, walk on it, or hold it in your hand. It's a vast expanse, not a physical entity.
* It's a relative term: "Sky" can refer to different things depending on context. Sometimes it means the entire atmosphere, other times it refers to the blue we see above us, and sometimes it even refers to the celestial objects like the sun, moon, and stars.
So, the sky is more of a concept, a way we describe the space above us, rather than a specific place or thing.
