A mirage is an optical illusion, not a hallucination. Both hallucinations and illusions involve a distortion of perception, but they have different underlying causes.
Mirage (Illusion): A mirage is a type of optical illusion that occurs when light is refracted, or bent, as it passes through layers of air with different temperatures. This bending of light can create the appearance of objects, such as water or oases, that are not actually present. Mirages are commonly seen in deserts or on hot pavement, where the ground is significantly hotter than the air above it, causing the light to bend and create the illusion of water or distant objects.
Hallucination: Hallucinations, on the other hand, are perceptual experiences that occur in the absence of external stimuli. They can involve any of the senses, such as seeing, hearing, smelling, tasting, or feeling something that is not actually there. Hallucinations can be caused by various factors, including neurological conditions, certain medications, drug use, mental health disorders, sleep deprivation, and other physiological or psychological factors.
In summary, a mirage is an optical illusion caused by the bending of light, while a hallucination is a sensory perception that occurs in the absence of real external stimuli.