Remember those old cartoons, where a character would be walking through the desert, run up and dive into a lake and then suddenly realise it was a mirage all along? You may think that mirages, such as the ones portrayed in the cartoons, are an optical illusion – this however, is not all true. Unlike optical illusions – which are visually perceived images, mirages can actually be physically photographed. It's the mind that creates the illusion and tries to reinforce the idea that there may be water in the distance. Since we have accepted the existence of mirages, we have learnt to distinguish the difference.
A mirage is a natural-occurring refraction phenomenon whereby light rays are bent to produce a displaced image usually in the distance. Mirages commonly appear on roads when the weather conditions are sunny, very hot and dry.