What causes mirages?

We see because the light strikes the objects around us and bounces, It travels through the invisible air carrying an image or picture of the scenery to our eyes. But when a layer of warm air is expanding like a balloon, it misplaces the image of the scenery and we see a mirage. Sometimes a layer of expanding air mirrors the scene and sends this reflection to our eyes.

Tricky mirages are caused by layers and pockets of air with different densities. In a pocket of dense air, there are more molecules of gas. In light air, the gases are thinly spread. In the summer, thin layers of air near the surface tend to warm up, expand and become light, If the air above remains dense and heavy, the scenery may be shifted around in tricky mirages.